Overfilled oil: Accidentally did that on my '79 Chevy 4x4, thought for some reason it was a 6-quart capacity instead of 5-quart. It doesn't see RPM, mostly just runs into town on occasion & shoves a plow around in winter, but there was oil coming out of it everywhere, even a puddle of accumulated mist on top of the air cleaner & finned M/T valve covers I added for humor. It runs factory breather & PCV.
This in addition to the traditional SBC habit of weeping oil at every seam, mind you.
With 5 quarts, that extra rustproofing stopped.
It's a Targetmaster crate deal, not too many miles, previous owner did that some years back.