Question for you.......

I assume you’re using a return style regulator?

Is that in the back or up in the engine bay?

When you’re doing the pressure/flow test....... was fuel still returning to the tank?

If so, perhaps a different regulator might improve the situation.

68 Satellite, 383 with stock 906’s, 3550lbs, 11.18@123
Dealer for Comp Cams/Indy Heads