1998 Chevy Silverado Fuel regulator or fuel pump?

I have a 1998 5.7L Vortec engine in my old restored pickup. Not a 1998. So recently it quit on me and will idle only after cranking it a long time. As soon as I step on the gas it quits.

I connected a fuel pressure gauge and the pressure is about 52 to 55 psi and it would immediately drop to 0 when the key/pump was turned off. This engine requires 60 to 66 psi, so I changed the fuel pump and it did not make any difference.

Then I used a vise grip to squeeze the return fuel line and turned the key on (engine off) to see a pressure of 61 psi. When the key was turned back off the pressure stayed at the 61 psi.

So first is this pump going to work for me and second is the problem the fuel reguator?

Should I buy a pump that pumps a higher volume to make up for the amount of flow the regulator is requiring?

If you can help me solve this I will gladly donate.

Craig