Now that you have it all primed, I'd touch up the bare spots with reg primer, forget etch primer. Then I would red scuff pad the whole thing and paint it.
I would have painted it bare steel, myself.

If your looking for a rattle can, this would be my suggestion.

The correct paint is this 9388 black paint. It has a very unquie finish, not not gloss, not flat. The Sem paint above is very close, imo.

I've sprayed it(lacquer) right over the factory metal dash frame that I just scuffed and sprayed and they have been in my cars for 5 and 12 years now.
So sure about the primer thing, because your dash frame is inside the car not out in the weather.