electrical gurus, i need help sizing an alternator.

If you don't run electric fans, or pumps and EFI, or a bunch of "big stereo" amps you could get by fine with a stocker

"The thing is" not really the output amperage, it's LOW RPM OUTPUT that makes the difference, and causes all the grief, IE bitching about low or no output at idle.

You should be "in overkill" for what you have I'd guess

If you still have the ammeter hooked up you might wanna read THIS

http://www.madelectrical.com/electricaltech/amp-gauges.shtml