If you're running a 270 GMC engine, somebody has done some modifications already. There's no telling how much butchery to the front crossmember and radiator mount there has been. GMC's are a couple of inches longer than 235's, and the fan tries to hit the radiator, plus the front motor mount doesn't line up right.
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
Love your enemies and drive 'em nuts!