i have not done any yet, but am planning on painting some of my interior pieces as well. they do make special paints for plastic, but it sounds like youre using an enamel, which could lead to cracking/ chipping. i think the plastic paints actually dye the plastic. if your SET on wanting the white, i know krylon makes a special primer for using regular paint on plastic without having it flake and chip. if you dont use a special primer, make sure you really scuff those plastic pieces well w/ sand paper to get the paint to hold. as always, a few coats would be a good idea. just curious, what made you decided on white? post pics of youre results!