You'll need a different (as in BIGGER) radiator, ditto on the exhaust system. None of the accessory brackets like power steering, alternator, etc., from the 305 will fit, so get everything you can from the donor vehicle. Bellhousing bolt pattern will be the same, not sure about motor mount brackets. You might need a torque converter with a different stall speed, assuming the truck has an automatic trans. The big block will pull a lot harder at low speed, so a lower stall speed converter will make it work better. If it's a C-60, it's probably a stick shift, but if you can get a Turbo 400 with the engine, drop them both in there!
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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