Can epoxy primer be used over Rustoleum rattle can gloss black paint?

I have been working on a car for a friend for a long time. I have refrained from using rattle can stuff except for a guide while knocking filler down. It pretty much all comes off and its just a dusting. I like the metal work, hate the finishing. Lets put it this way, if its my junk i’d paint it with a mop.
I met a fellow that hates metal work and likes filler work and paint. Was reccomended by a paint supplier. My job now is to assemble it and line up panels as best as i can. Then ship it.