Here's pic of mine a few years back when I painted the rims as one of my very first mods.



I cleaned the rims first, then scuffed the surface with a scotchbrite, cleaned again with alcohol to remove any sanding residue and let dry. Taped off the tires and shot with hi temp gloss black engine paint. They also make a hi-temp clearcoat for wheel in a spray can which I have used. You can scuff and clean your color coat before applying the clear gloss for good adhesion.

Just remember after you paint the wheels keep the spray wheel cleaning solutions FAR,FAR away as they will kill the gloss finish in a hurry. Just good ole soapy water and quik detailer after drying will keep them shiny and make brake dust easy to remove.