I believe it might be possible to adapt a larger diameter version of the lip seal to GMC sixes by fabricating a seal holder that surrounds the flywheel flange on the crankshaft and bolts to the back of the engine block. It would require a seal about 6 inches in diameter to work on a GMC engine, I believe.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
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