this what I would do, oem and easily sourced parts. I've seen a few pics and threads on the corvette boards of the mechman failing and long wait times for replacements. not a big deal when your corvette sits in the garage most of the time and they do look nice all billet and powered coated. not great when you're away from home. I do road trips so have stayed with a oem and lessened the load with by changing to pwm brushless fan and things like that.
as said above, definitely make sure your alt wire can handle the extra current. my old 96 I put the larger case diesel alt on it after going electric fans. charged great but the alt wire was warm to the touch. had to step up wiring gauge.
ict makes a very nice atl spacer if you ever need to run a larger case alt in the stock bracket. all things being equal, larger case the larger the rotor and stuff, more efficient and cool better than getting the same power out of a smaller package.
just info I've found looking around at alternators.