Etch Prime?

[RustyBus]

Ok so when rubbing down a previous poor respray I have rubbed through to bare metal in places, also I have repaired some areas. Do I just etch prime the bare metal areas, feather the edges and then high build primer over every thing, or do I etch prime over the old paint as well? All of the old paint has now been flatted back so I don't think adhesion will be a problem.
Arran

 

[jaykay]

just useh/b primer as long as you do it right away before any rust gets started.