How to Repair Auto Body Kits

1). Sand in and around the damaged area using 180-grit sandpaper, smoothing the edges until no jaggedness can be felt with your hand. Using a plastic squeegee, apply a 1- to 2-inch thick layer of flexible body filler over the damaged area. Let the filler dry for a full hour.
2). Use the 180-grit sandpaper to smooth the filler, until it is almost level with the surrounding surface. Then, sand it completely smooth with the 220-grit sandpaper.
3). Cover the areas surrounding the repair with masking tape and paper. Place the tape 5 to 6 inches away from the outside edges of the repaired area, and then add masking paper to the tape. Cover at least two feet of surface space that surrounds the repaired area, so when the paint is sprayed, none gets splattered onto areas that don't need it.
4). Apply a thick coat of primer and let it dry for 30 minutes. Sand the primer smooth with 800-grit sandpaper. Spray 3 to 4 light, thin coats of paint, holding the can 6 to 8 inches from the surface. Spraying thick coats can cause runs in the paint. Wait 10 minutes between coats. Spray 3 to 4 thin coats of clear-coat paint, using the same techniques as with the color paint. Wait a full day before handling the area or driving the car.