Cadillac, Olds 98, and a few big Pontiacs ran a heavy duty generator with a 45 amp capacity. The best way to identify that one is to look at the rear end frame- - - -it it's got a ball bearing there instead of a bushing it's the heavy duty model. George is correct about the current regulator needing to be adjusted to match the generator capacity. Most of the short housing Chevy 12 volt units were somewhere in the 25-30 amp range. The stepped-frame long ones were in the 35-45 amp category, with maybe a few heavy duty big truck generators going 50+ amps. Those are usually also bigger in diameter, however.

"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!