1960 P/U oil problem

I have a 1960 chevy c-10, iline 6 235ci and had the engine completly rebuilt profesionally, and restoring the truck at the same time, its been maybe 3 yrs since its been rebuilt but has never really run, we would start it for 30 secs or so then shut it down. about a month ago we let it run so we can break in the cam, after 3 min of running, it shut off, then it would not start, we loked at the temp gauge, and it was hot, so we thought it just over heated we checke the wter lines and everything was ok. then were remebered we replaced the oilpan seal and thought we forgot to put oil back in, so we check that and there was oil but just a hunch we oppened up the fill plug and looked in and everything was dry. so we pulled off the oil filter and it too was bone dry, so we replace the oil pump, and today we tryed it again, and still no oil anywhere. HELP!!

When the engine was rebuilt , was an oil sump pickup installed and if so , check to make sure that it did not shift position and is being blocked by the pan or something

Oh , was the oil pump primed as well....... to do this you need to remove the distributer , the entire unit and take a long flat blade screw driver and cut the handle off and insert it into a drill..... then take a flashlight or trouble light and look down inside the hole where the distributer came out of and line up the flat blade screwdriver with the slot in the oil pump and rotate run the drill (forward) and have someone watch the oil pressure gauge untill you get pressure. Once you have oil pressure you can reinstall the distributer assembly. Hope this helps.