Couple extra pictures. The stud is something you need to add when swapping the bigger V6 in a pickup, it bolts onto the pickup motor mount. On the truck V6's there is an oil retour (for the air compressor possibly?) I made one from an old oil galley plug which has a 7/16 UNF bolt plug welded to it. I shortened the plug so it was flush with the block.
The next picture is the bypass valve of my own design. it is set to open at about 14 psi and fits into the spin-on oil filter. It uses a plunger that gives room to 4 holes. The washers are shims to 'calibrate the pressure'. Due to the holes it opens and closes gradually and does not chatter on its seat. Hope it makes sense