Hi Moses,
First of all, thanks for all of your help on this frustrating issue.
Answers to your questions above :
The lower prime point I used is the oil pressure sending port on the block. I did rotate the crankshaft by hand, and got oil at the rocker closest to the firewall only. Also, got oil flow into the oil filter canister.
I could hear the oil pushing into the oil pan, and about 3 quarts flowed in quite quickly.
I also connected the priming tank to the oil pressure gauge, to be sure the gauge (new) is not faulty and the connections are tight. I got a reading of 40 psi, which is what I put in the tank.
There is no plug on the oil pump to serve as a priming point, and I haven't yet tried priming it through the pressure regulator. By virtue of the fact that the oil filter canister had flow, the pump must be working.
Having seen the flow at the oil filter, I reassembled everything and checked the gauge again.....no oil pressure turning over by hand, or with motor running (briefly)
I will try priming through the square headed plug in the block tomorrow.
Whit