Here is what I've done so far.
Drained tank. Strained fuel. Clean no trash. Foam isn't blocking outlet. Used a paper paint strainer.
Blew lots of air thru fuel line. Clean, straight and no kinks. Almost all 1/2" aluminum tubing except where it comes out of the tank to the filter and from the regulator to both carb inlets..
New Wix fuel filter in the Fram housing.
New Blue Pump and Regulator. Cleaned undercoating off and removed the paint with an air grinder. I wanted to make sure the extra ground wire had a good ground.
Did away with relay on fuel pump and went back to directly wired.
Still wants to lose pressure.
Another new Holley regulator that I had.
Still losing pressure.
Out of curiousity I disassembled old pump. No trash on screen and vanes free. So I'm sure it's good.
I'll look into it some more tonight.