… next time if you have the oil pan off, just take the 2 hex bolts out that hold the oil pump in place and remove the oil pump.
For Tools you will need a cheap rotary pump, a viable speed hand drill, two line clamps, a small 1 gallon bucket with sealable lid and put 2 quarts of cheap 30 wt oil in it and one of those black plastic concrete mixing pan buckets that are usually 2 ft x 3 ft found in hardware stores.
Obtain a 3/8 inch O.D. clear plastic tubing about 8 feet long. Stick one end up into the oil route line that the oil pump sets up agains when in place and secure it with a vis-grip or duck tape. Take the other end of the tubing and cut about 2 1/2 feet off of it. Attach both ends to the cheap rotary pump. Place the black concrete mixing pan/bucket under the block so it will catch any falling oil from inside the block and oil pump area. Now attach your drill to the rotary pump and fire up the drill slowing at first then increase once you have made sure the tube going up into the engine is secure. This will drive the oil up into and past the oil filter boss/check valve, up into the oil galley ways lubricating everything and will do it will adequate pressure. Turn the drill for until the oil in your reserve 1 gallon bucket is about 3/4 empty. You will be catching the rest of the oil in your concrete mixing pan bucket set below the engine block.
When done, get a suitable sized plastic container with lid so you can store the plastic tubing and rotary pump. Filter the oil from the concrete mixing pan back into the 1-gallon bucket and put its lid on the top so you can keep the oil and use it again when having to prime an engine next time.
This method can be used by just removing the oil boss and filter assembly/valve and inserting your plastic tube into the side of the block as this will route your rotary pumped oil up into the engine oil gallery as well.
Thanks in Advance!
Born Buick - " I like things just the way they were and drive-em just the way they are "