** repost (does anyone know about this???)

A while back I got my drivers side mirror knocked off in an accident. I went to the car dealer and bought a GM replacement part. The mirror was exactly the same as the old one, but it was unpainted. The original one had a deep black gloss look to it and didn't look plastic.. but i'm sure underneath it is also plastic. Anyway, I know the best way to do this would be to take the car to a paint shop and have them paint it. Just for another option how would I go about painting it myself. Lets just say I was going to do both sides so they match. Both would be painted black. Would I start by sanding both of them.. and if so, with which type of sandpaper... afterwards I don't see what else would be left except for a few thin coats of black and then 3-7 thin coats of clearcoat??? right? I have read all these articles on painting interior panels on these message boards... would there be any reason why I couldn't paint these and get decent results?? Any help would be greatly appreciated. Thanks.