I used a product called "all purpose condition and cleaner" made by Tannery. Works on leather, vinyl, rubber, trim, & fiberglass. Since applying it, the louvers have stayed dark black ever since along with the engine cover, windshield trim, side moldings, the rocker panels, spoiler, quarter panel intakes, & the under body. And it hasn't washed off since. Although I can't say the same for the dummy vents behind the doors and the side mirrors which turned gray again, and the ERM frame around the licence place which is so porus it just attracts dust anyway. But since it worked so well on the louvers alone, you may want to try it for a while as a substitute for painting. -Robert vin 6585 p.s. I have a white streak on my back bumper which looks like that stuff that meter maids rub on your tires. How can it get this stuff off? I know a long time ago someone else on the list had the same problem, how'd you fix it?