6 or 8 cylinder? The GMC six was a couple of inches longer than the Chevy, so the front crossmember will have different engine mount holes, and the V8 GMC's used Pontiac engines, so the motor mount holes and/or crossmember positions might be a little different.
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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