"It's very obvious you've never been inside a GMC engine. It's already got full pressure oiling, a huge oil pump that flows far more oil than a stovebolt Chevy, full flow oil filter, and aluminum pistons- - - -they were all built that way."
Jerry, I do have a comment about your previous post.
I have never seen a GMC engine of that era that came with full flow oil filter filtration, only bypass from the Factory.