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.
