72 318 Scamp. Low oil pressure 1 minute after startup.

The engine now has been taken totally apart. This what I found. Rod bearings .020 under, Main bearings. 030 under. Crank isn't in terrible shape. I could maybe polish it. Can't feel grooves in it. Looks like it was possibly rebuilt twice. Say this from looking at the date on the road vs the main bearings.
The nuts on some of the rods are a different type. Don't know why except that whoever rebuilt this engine used whatever he had laying around just to make it work.

My last problem is in the block. Look at the picture posted. Looks like a possible internal hole in the block. What do you guys think?

My brother in law has a 360 that he got at an estate sale complete for $75. He took the starter off it and said that I could have it for free! If this engine is going to cost a lot to fix I may go with his offer. As far as I now the block has the same dimensions as a 318. This is I think, a 1971 block.

Here are the latest pictures.

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