Oil Galley plugs at Camshaft

A 50% loss of oil pressure from that plate seems damn near impossible to me. You can leave a plug or and have that kind of pressure.

That's unreal.
IMHO, there is nothing guaranteeing that plate will always seal true to the block. It is machined flat on the back but who knows for sure. I can easily see one getting a kink, or a burr on the edge that raises it in one corner, from being dropped, poorly machined at the factory. etc. And the bolts are spread too far to make sure you get a good seal.

Thanks for all the input.

I think we will just take those pipe plugs out of there and put the timing tensioner on with the passenger side galley covering drilled out with a 1/64 hole.

The 318 always had great oil pressure and it had nothing in those galley holes.
OP, IMHO, you are asking for potential trouble by not putting some short plugs in there. It's the same reason as above... the plate for the tensioner is not at all designed to guarantee an oil seal. One bit of warpage, a burr in the wrong place, etc., and you are losing pressure. I don't think those tensioner plates are machined flat on the back like the original plates tend to be.

Are the threaded plugs all the way in? If so, I'd find some shallower one, or grind those down 'til the fit under the tensioner plate. Then drill an oiling hole on one plug (in the driver's side IMHO, since any loss there is less critical to the engine) and another hole in the cover plate in front of it, or use a drilled jet like suggested.

BTW a 1/64" hole is only about .015" diameter.....maybe you meant 3/64" ?