Any recommendations on fuel setups 502,mega blower,chiller,2 750 Holley's. I'm running fuel feed to water fuel separator. Then into fuel pump and 1 out to regulator and then from pump out to regulator. Then 2 out from regulator to carbs . Fuel pressure gauge is real choppy. I think I'm leaning out . Can get out of the hole lean pop.

Sounds like more of a carb issue to me.

What size line are you running from tank to filter to pump? What pump are you running?

Holley black

Fwiw - my boat with a 502 single carb came with a Holley red pump(97gph) and it would drop to 3psi at anything above idle. I have no opinion as that's just information.

can everything from tank to carb, remove anti siphoning valve, make sure fitting is min 3/8, 1/2 better, use something like a aeromotive A1000 pump, filter before, filter after, return regulator w/return to tank, that would be correct way.