Do you have a multimeter? If so (and you should, they'll save your ass) you should pull the harness that plugs into the back of the alternator and runs up to the voltage regulator. I did on mine after I went through a few alternators from kragen/oreillys and a couple regulators before I realized their original alternator had fried the wiring in that little harness. I just tested the ohms on each wire till I had one that was wildly different than the others, and ended up finding another 1 or 2 that were none too fresh.
