Epoxy over bare metal, filler then more epoxy, or urethane?

[nikwho]

Okay, title may be confusing. So, my truck was blasted/sanded down to bare metal. I sprayed entire truck, entirely disassembled, with epoxy primer. So, I'm working on a little bit of my body work. I've applied some filler (Evercoat Rage Gold) over the epoxy, adhering to redcoat windows, need to scuff, etc.

My question is this: When I and down filler and get down to bare metal around the repair, what is the ideal next step?

• Do I continue to reapply epoxy over ANY exposed metal, prior to moving forward with any other product? That feels like an excessive level of spraying epoxy, applying filler, sanding, spraying epoxy, applying more filler, sanding more...

• Do I continue to fill, sand, fill, sand until I'm happy, then apply my urethane primer over entire panel?

• Do I continue to fill, sand, fill, sand until I'm happy, then reapply epoxy over that area, covering any bare metal, then apply a few coats of urethane primer over epoxy and begin my final blocking?

Then, later one, when final blocking, what is the recommended course of action if I accidentally sand through? Reapply urethane before allowing myself to cut through epoxy? I worry about this step because I made the mistake of buying both grey epoxy and grey urethane primer, so I dont want to unknowingly sand through urethane and epoxy, to bare metal again.

Do I need to tint my urethane, or buy a new color of urethane primer, that stands out against the grey epoxy?

I hope that this makes sense.

Thanks for any help/advice!

Nik