<VV> GM Help needed, possible Corvair related

[FrankCB]

Grant,
What's the charging voltage on the system at engine speeds above idle?  Plug in a voltmeter (or DMM set on DC voltage range) into the cigarette lighter socket.   If it's not above 13 volts, then you're not charging the battery and the "gen" light is responding correctly.  If it reads above 14 volts, then the charging is probably OK, but the mechanism turning on the light is faulty.
Frank Burkhard 

In a message dated 01/05/10 15:35:13 Eastern Standard Time, gyoungwolf at earthlink.net writes:
I am trying to figure out why the "Gen" light is on in my 1972 Cadillac. I have a newly rebuilt alternator, new battery and new wiring back to the firewall. I hooked up a simple battery/alternator testor and it shows that everything is fine. 
This problem started shortly after I replaced the alternator the first time. 
I disassembled it and found that a large plastic piece on the rotor had broken and sent pieces throughout the windings. Installing the second USA rebuilt alternator did not solve the problem, however. Any advise on where to look for the whatever is keeping the light lit all the time? 
Thanks, 
Grant