I was talking about a threaded plug (see foto where the 5/16" allen wrench is sticking out of the block). Did not even know about this other one toolmanmike is explaining.
I looked for this "secret" pressed in plug and found it still in place, located about 2 1/4 inches below the oil port hole in the block/rear main cap that is fed from the oil pump. I'm not about to remove that sucker. Yes, you do learn something new every day and often times thanks to members of this very forum.
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