What a wide body kit does and what you need before starting

A wide body kit for the R230 SL63 Black Series replaces the standard fenders, side skirts, and sometimes the rear quarter panels with wider versions that extend the car's track and change its visual stance. The kit does not alter the suspension geometry or handling—it is purely a visual and aerodynamic modification. Before you begin, you need the kit itself (usually sold as a complete set from manufacturers like Lorinser, Brabus, or AMG), basic hand tools, a jack and jack stands, a torque wrench, and ideally a lift or level concrete floor.

The R230 SL63 Black Series sits lower and wider than earlier SL models, which means fitment is tighter and panel gaps matter more. You will also need to remove and reinstall the wheels multiple times, so having a second person present makes the work faster and safer. Most kits come with installation instructions specific to your model year, but those instructions often skip steps or assume shop experience—this guide fills in what actually happens during the install.

Key Takeaways

  • Wide body kits for the R230 SL63 require removing the factory fenders and side skirts, which means disconnecting the door seals, trim pieces, and sometimes wiring for side marker lights.
  • Panel gaps and alignment take longer than the physical bolting—expect to spend time adjusting fender height and door-to-fender spacing before final torquing.
  • The rear quarter panels on some kits require cutting or removing the rear wheel arch trim and may need welding if you want a permanent installation.
  • Torque specifications vary by kit manufacturer, so follow the instructions that came with your specific kit rather than guessing at bolt tension.
  • Paint matching and clear coat protection are separate from the mechanical install and should be done before or after the kit is mounted, depending on the kit's finish.

Removing the factory fenders and preparing the body

Start by removing both front wheels and setting the car on jack stands. Remove the plastic wheel well liners by unbolting them from the fender and door jamb area—these are held by plastic clips and bolts, usually 8 to 10 mm. Once the liners are out, you can see the fender bolts clearly.

The front fenders on the R230 are bolted along the top edge (under the hood), along the bottom edge (inside the wheel well), and at the door jamb. Unbolt the top edge first by opening the hood and removing the bolts that run along the fender-to-hood line. Then remove the bolts along the bottom inside the wheel well. The door jamb bolts are the trickiest—they sit where the fender meets the door, and you may need to remove the door seal rubber to access them fully. Once all bolts are out, carefully lift the fender away from the car. It is heavier than it looks, so have a second person help or support it on a padded surface.

Before installing the new fender, clean the mounting surface on the car body. Remove any old sealant, dirt, or corrosion. If the new fender comes with a protective film or tape, leave it on until you are ready to final-fit it. Do not bolt it down yet—you will need to check gaps and alignment first.

Installing the new fenders and checking panel gaps

Offer up the new fender to the car and hand-tighten the bolts just enough to hold it in place. Do not torque them yet. Now comes the critical part: checking the gap between the fender and the door, and between the fender and the hood. On the R230, the factory gap is typically 3 to 4 mm all the way around. Most wide body kits are slightly wider, so the gap at the door may be tighter or the fender may sit proud of the hood line.

Use a feeler gauge or a piece of stiff cardboard to measure the gap. If the gap is uneven—wider at the top and tighter at the bottom, for example—the fender is tilted. Loosen the bolts slightly and adjust the fender up, down, or forward until the gap is consistent. This usually takes several tries. Once the gap looks right, tighten the bolts in a cross pattern (top-left, bottom-right, top-right, bottom-left) to avoid pulling the fender out of alignment. Torque to the specification in your kit's instructions, typically 18 to 25 Nm for fender bolts.

Repeat this process for the other side. The two fenders should be symmetrical—measure the gap on both sides of the hood to confirm. If one fender sits higher than the other, the car may not be level on the jack stands, or the body itself may have a slight twist. Adjust the stands and recheck before final torquing.

Removing and installing the side skirts

The side skirts on the R230 run from the front wheel well to the rear wheel well along the rocker panel. They are held by bolts at the front (near the fender), in the middle (under the door), and at the rear (near the rear wheel well). Some kits also have clips or adhesive, so check your instructions.

Remove the wheels again for easier access. Unbolt the front end of the side skirt first—there are usually two or three bolts. Then unbolt the middle section. The rear section may be glued or clipped, so gently pry it away from the body. If it is glued, use a heat gun or hair dryer to warm the adhesive and make it easier to separate. Once the old skirt is off, scrape away any remaining adhesive with a plastic scraper.

Clean the mounting surface and offer up the new side skirt. If it comes with adhesive strips, peel the backing and press it firmly into place. If it is bolted, hand-tighten the bolts first and check that the skirt sits flush against the body with no gaps or high spots. Adjust as needed, then torque the bolts. If the kit uses both bolts and adhesive, let the adhesive cure for 24 hours before driving.

Handling the rear quarter panels and wheel arch trim

Rear quarter panel kits vary widely. Some bolt on like the fenders, while others require cutting or removing the existing rear wheel arch trim. Check your kit's instructions carefully before you start—this step can range from 30 minutes to several hours depending on the design.

If your kit requires removing the rear wheel arch trim, unbolt the trim piece that runs along the top of the rear wheel well. It is usually held by bolts inside the trunk and along the side of the car. Once it is off, you can see whether the new quarter panel bolts to the existing body or whether it needs to be welded. If welding is required and you are not comfortable doing it yourself, this is the point to stop and take the car to a shop. Welding a quarter panel incorrectly can compromise structural integrity and rust protection.

If the kit bolts on, follow the same process as the fenders: hand-tighten, check gaps and alignment, then torque to specification. Rear quarter panels are often wider at the wheel well, so make sure the gap between the panel and the rear door (if applicable) is even. Once everything is torqued, reinstall the wheel arch trim and any other trim pieces you removed.

Reconnecting trim, seals, and electrical components

As you removed the factory panels, you may have disconnected door seals, trim clips, or wiring for side marker lights. Before you put the wheels back on and call the job done, reconnect everything. Door seals should sit in the groove where the fender meets the door—if they are pinched or twisted, the door will not close smoothly and water may leak in.

If your car has side marker lights integrated into the fender or side skirt, make sure the wiring is reconnected and the lights work. Some wide body kits move the marker light location, so you may need to drill a new hole or use an adapter. Check the kit instructions for guidance.

Reinstall the plastic wheel well liners. They protect the underside of the fender and help with aerodynamics. Make sure they do not rub against the tire at full lock or full compression. If they do, trim them slightly with a rotary tool or knife.

Final checks and paint considerations

Before you drive the car, do a full walk-around and check every gap and bolt. Open and close the doors and hood to make sure nothing rubs or binds. Check that the wheels clear the new fenders at full lock and full suspension travel—some wide body kits reduce clearance, especially if your car is lowered.

Most wide body kits come in primer or bare plastic and need to be painted to match your car's color. Some shops paint the kit before installation, while others install it first and paint it in place. Painting before installation is usually cleaner and easier, but it means you have to be more careful during the install to avoid scratching the paint. Painting after installation means you can blend the edges perfectly, but you risk overspray on the glass and trim.

If your kit came with a clear protective film, leave it on until the paint is done. Once the paint is cured, remove the film carefully and explore a ceramic coat or wax to protect the finish. The new panels will be more exposed to road debris and UV than the factory paint, so protection matters.

Frequently Asked Questions

Do I need to adjust the suspension or alignment after installing a wide body kit?

No. A wide body kit is purely cosmetic and does not change suspension geometry, ride height, or wheel alignment. However, if your kit is significantly wider than the factory fenders, you may need to check that the tires do not rub at full lock or full compression. If they do, you may need to adjust camber or reduce ride height slightly.

Can I install a wide body kit myself if I have never done bodywork before?

Yes, if you take your time and follow the instructions carefully. The bolting and unbolting is straightforward. The hard part is getting the gaps and alignment right, which requires patience and a willingness to redo work several times. If you are uncomfortable with any step—especially welding or electrical work—stop and take it to a shop.

What if the new fender does not line up with the hood or door?

Loosen the bolts and adjust the fender position. Fenders can usually move up and down, forward and backward, and tilt slightly. Make small adjustments and recheck the gaps after each one. If the gap is still wrong after several tries, the fender may be damaged or the car body may be out of alignment—have a shop check it with a measuring system.

Do I need to remove the doors to install a wide body kit?

No, but you do need to access the bolts where the fender meets the door jamb. You can do this by removing the door seal rubber and reaching in, or by opening the door fully and working around it. Removing the door makes the job easier but is not necessary.

How long does a complete wide body kit installation take?

For someone with experience, 8 to 12 hours spread over two or three days. For a first-timer, 16 to 24 hours or more, because you will spend time adjusting gaps and troubleshooting. If the kit requires welding or extensive trim removal, add another 4 to 8 hours.