1995 Chevy Astro doesn't start

1995 Astro 6 cylinder VIN W. Vehicle was running fine until it started going uphill then it lost power and died completely. Fuel pump was changed 2 months ago. Just changed the fuel filter and ignition module in the distributor. New cap and rotor as well. Shot some engine starter down the intake and van started for a couple of seconds and then died. Performed fuel pressure test. Initially key on and engine off: 22 psi. Momentarily key off then key on 32-36 psi. Engine cranking 36-38 psi. Immediately after cranking, you can hear the pump running, tops out at 38 psi until pump kicks off and drops to zero. Fuel pressure always dropped back to zero almost immediately at the completion of each fuel pressure test. I suspect a bad fuel pressure regulator. Is there anything that I am missing? If not, how difficult is it to replace the fuel injection unit or should I just get it towed to a dealer and let them fix it?

Thanks in advance,
Rich