A little "off topic" question for you great electrical guys ???

I have rebuilt a number of the old 10si and 12si delco alternators and one common issue is the diodes. get yourself a set of heavy duty diodes from a local electrical rebuilder made for something like a 120 amp unit and that will cure the common voltage drop problem. as far as the spiked ones they usually end up being something inside the alt. not making a good connection so the regulator thinks its an open circuit and starts overcharging. i have had good luck with the replacement regulators from borg-warner, they seem to make a quality part.