Go buy some SEM Adhesion Promotor and some SEM Landau Black spray paint. I recently sprayed my A-pillars, kick panels and lower dash trim pieces with those products and they turned out great. The Landau Black is a very close match to the original gloss of the plastic.
Here's a picture of what the kick panels looked like before being sprayed.
I washed them 4 times before spraying the Adhesion Promotor. Once with soap/water....once with Simple Green....once with mineral spirits and finally with a wax/grease remover. I sprayed the Adhesion Promotor per the dirrections on the can. Follow the dirrections exactly. After the final coat of the Promotor and after waiting 20 minutes, I applied a few mist coats of the Landau Black. If you just mist the paint on, once it dries, you won't be able to tell that it's paint. Get it on too thick and it will look painted.
Here's the finished product.