Hoping someone can give me a clue here...
My 71 had the original voltage regulator setup. I had a spare 10 SI internally regulated alternator (63 amp) that had gone bad. I picked up a rebuild/upgrade kit from here (
http://www.alternatorparts.com/alternators_gm.htm) as well as a conversion harness from here (
http://www.wiringharness.com/custommods.htm). In two hours I rebuilt my alternator and installed it along with my conversion harness.
Unfortunately, it did not get rid of my lights dimming at idle in gear and flaring on acceleration. I checked voltage at the alternator and at idle and it was putting out roughly 13 volts...if I revved the engine slightly it jumped to 13.65-14.20. I checked it at the battery and had roughly the same readings....
Any ideas?