Air Gap intake back form media blast.. clear.. paint or run as-is?

I paint all my motors including cast iron intakes together. Final cleaning before painting is done with acetone and I had never had a peal. I also use acetone for gasket installs. Do not remember which heat paint(clear) I used for my one aluminum intake, but I recall you had to bake it in an oven of some sort (My wife was pissed at me for some time). LOL.... It looked good for many years, but now showing its age (34 years) as the rest of the motor. Also no pealing.