I have a 302 Ford block code D90E-6015-E3A I am rebuilding. I know the 302 is a 1979 to 1984 period block. I cannot figure out what the holes in the back passenger side of the block are for. 1 hole is in the rear main and it aligns to a hole just below the deck on passenger side rear of engine. Above the hole near the deck is a thread hole on the machined surface. I am guessing it is emission related and I can plug the bottom hole with an oil galley plug. The hole below the deck should be fine covered with rtv as it just keeps dirt out of bellhousing. I just wanted to know what it is used for? Attached is a picture the BLUE arrows point to the holes.