If you have a 63-72 alt. that uses the external reg. any one in that era will work. I would put the alt on & make sure the wireing is right. The reg. on it may be all right. If you put it on & it still doesn't charge you can check it like I described earlier. When it's all done & working you should put a voltmeter on it & make sure it charges between 13.8 & 14.5 volts.
