I've never used Prime so I can't answer that specific question. I have had pretty good success using something mild like VM (Vanilla Moose) with a polish pad on those shiny black plastic trim pieces and black mirror housings. I also did the same with some ZAIO recently on a polish pad, so I would think Prime might also work well. If they are really bad you might have to step up to something a little more aggressive. The ones that I have done seem to correct pretty easily, but are also more prone to marring from incorrect wash techniques.