What I did for my air cleaner was clean it up and remove all of the dirt/rust etc. I did not go so far as to bead blast it. I then shot it w/ semi gloss black Rustoleum as a base. I then shot it w/ black wrinkle paint (not the cheap Plastikote stuff). I picked up the trick of the heat gun here on Moparts. It causes the paint to start wrinkling quickly and if done slowly and evenly will get a uniform wrinkling over the entire air cleaner. I then let it dry in the sun for several hours. I thought it came out pretty nice as this was my first ever attempt at it.