Clean, clean clean and then clean some more. The things have 20-30 years of Armorall and various other polishes and chemicals added to them. You need lots of soap and water, degreasers and even wipe it down with some laquer thinner using a scrubbie. SEM does have some prep products you can use to. It's like painting your car, it's almost all in the prep. When I get down to the spraying part, I spray 3 light coats to get good coverage then let it dry untouched for about a week. Do a google search on dying plastic interior pieces. Lots of good how-to's there as well as on Welcome to FourEyedPride.com .