AMC 360 - Lost oil pressure

Looking for some guidance. Last time I drove the CJ a couple months back I remembered looking down and seeing no oil pressure. Not knowing if this was a sensor issues or real problem, I drove home and parked it. Two weeks ago as weather started warming up, I started her up and saw no oil pressure... cut off quickly. I found the oil to be roughly a quart low (a quart took it back to mid between high and low).

AMC 360 (from 80 Grand Wagoneer w/ 80k miles) Rebuild 8000 miles ago as follows...
Bulltear oil relo, cam gear set, HEI
Rear main oil bypass
New oil pump kit
40 over pistons
Edlebrock performer intake, cam, lifters, spring & retainers, timing set
Mobil1 10W-40 synthetic with K&N filter

Oil pressure was in the 50 psi range cold and dropped to 15-20 psi warm (hard to judge, my gauge seemed to drop off to 0 much below 20 psi) prior to the issue. I had good intentions of swapping to a mechanical gauge to determine what my pressure really was... never got around to it until this issue popped up.

So after reading some postings on here...
1) Swapped to a mechanical gauge... NO pressure, wouldn't even blow oil out of the tube
2) Drained the oil into a clean pan... no real indications of metal or filings
3) Removed the oil relo plate... Will take another set of measurements, one side of the main gear would pass a 0.0015 shim with a little effort, the other side would pass 0.005+. Also, the oil pump seemed dry-ish, there was a little oil in when the plate was removed but not more than ~15% coverage of the gears
4) Removed the oil pan... all lifters in place, dredged the oil pan with a magnet, nothing picked up. All pistons have oil on the skirts although #1 has a very fine non magnetic grit in with the oil. All cylinders have honing markings.
5) Removed valve covers... Other than not much oil, nothing out of the ordinary. Droplets on springs and lifters, but generally little standing oil.

Worth pulling the intake to check the oil galley plugs? Or can this be seen with a borescope?
Is it possible I starved the pump and never regained pressure?

Any recommendations on next steps?

Thanks

Dan

{Edit} Measured the oil pickup clearance at right around .300. When installed there was no gasket, just ultra black sealant.
{Edit 2} Meant to mention I have the oil filter mounted below the front frame cross member and behind the bumper. There is about a 1" drop from the relo plate to the centerline of the filter which is mounted horizontally. The outlet of the filter goes up into an oil cooler mounted behind the radiator. Then down back into the relo plate.

First thing I'd try is re-priming the oil pump. I usually do it by removing the oil filter and squirting oil into the pump with an oil can. If you have the pump cover off, pack the gears with vaseline or white grease. If there is oil in the pump gear cavity, it should draw oil from the pan. You can pull the distributor and spin the oil pump with a screwdriver shaft chucked in a drill.

Bob
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