Where did you source the bad alternator? I've had bad experience with rebuilds from the discount auto stores (Auto Zone, O'Reilley's, Advance, etc.
I once drove 50 miles to put a rebuild on daugher's car, late on a Sunday night, in blowing snow, only to have the "new" unit go up in smoke within 30 seconds of start-up. Had to squeeze 5 college girls, plus wife and myself, in our crew cab. Took the offending piece back and got one from a source I trust.