If you own a coupe with the extruded black rocker panels and have chips or scratches in them, you can make them look new again.
For shallow or minor chips and scratches (1/8" or less) WET sand the panel with 180 grit paper, follow with 220 or 240 and finish with 400. Paint with a semi-gloss black spray. They will look like new. For deeper scratches sand as above, then fill with glazing putty. Sand again and paint.
WET sanding is important. As these parts are coated plastic, dry sanding is not successful. It's gotta be WET!
From: Randy T. Agee