I've been working on my 71 Demon for a few years now and about ready for final prep before laying down the base/clear. The car has had lower quarter patches welded in and various small dings filled. Currently, the repaired areas have been primed with rattle can Rustoleum Auto Primer (I know, not the best stuff, but not the worst either IMO). There's a few place of bare metal exposed now after I've blocked it out. Do I spray the entire car with Epoxy primer, or go straight to high build 2X Urethane? If epoxy, how much of the rattle can primer needs to be sanded off first? Going for a show worthy finish, but will be driven regularly.