I have been trying to diagnose a charging issue on my 71 for weeks now. The battery will show 12.6V when the car is off then drop to around 11.8 when the car is running. I'm assuming this means the alternator is not charging the battery. I got the old alternator checked, it failed so I bought a new one from Napa. Still have the same problem. The number 1 and 2 wires off the alternator go to the old external voltage regulator and the other wire on the alternator goes to the positive battery post on my starter (My battery is in the trunk). Can the voltage regulator cause the alternator not to charge the battery? I recently replaced the radiator core support which the voltage regulator is attached to. Is it possible the regulator is not getting a good ground from the new powder coated core support? Do I need a new regulator? Or can I just remove the regulator and get an internally regulated alternator? Thanks guys, I finally want to get to the bottom of this.