I hate to mention this but the Ford specified oil pressure for these engines is 35-40 p.s.i.

The bore marks are odd, I've only seen something like that on engines that have been sat with water in the bore, leaving pitting corrosion marks. I have seen wear on a main as you showed, on two occasions. One was a spec of grit on the shell back which must have been there from the build and the second was a burr on the edge of the bearing bore in the block which looked like it had been done during the piston fitting or removal as there was a matching witness mark on the rod. As for line boring the block / bearing caps, normally that's done once when the engine is built in the factory, you'd really only do it again on a competition engine that was being fitted with forged steel caps. If the crank gets ground then the mains oversize shells are the same on the outer diameter and smaller on the running diameter to match the grind. Worth checking if there might be potential losses on the cam oil feeds, I took an A Series BL engine apart where a previous owner had drilled out the cam pedestals and head, presumably to reduce wear or noise, which lowered the bottom end pressure enough to cause premature liner wear and big end failure. I've seen bike engines that have oil restrictors to balance the flow around the galleries, in one case sneakily in centre of a head dowel 🤨 I know next to nothing about Ford engines, to me a Pinto is how to order beer in a Japanese Pub.
Anyway, sounds like you have plenty of options to be able to build a reliable engine without spending a fortune. Hope it works out.