71' C-10 cutting out intermittently

[Hennyhog]

Hello all,
I've been trying to rectify this issue for about a month now and it is still kicking my AZZ. When driving, the motor is cutting out like loss of fuel, not running on all cylinders, and loss of power. I pull over shut it down for a minute or so then take off with no issues. It may happen 5 minutes into a cruise or 45 minutes. Here is what I've done so far.

New fuel tank (filters kept getting clogged thought I solved problem...nah)
Clear fuel filter
Changed over to HEI last week (REALLY thought I solved it this time...nope)
New plugs

I guess what I'm going to throw against the wall next is could it be a problem with the fuel pump? Can a mechanical pump fail intermittently?

Or could it be plug wire that fails/misfires intermittently? It's a 350 with a Holley 650 dbl pump if that helps.

As always love the feedback and what you guys suggest!

Henny