Charging light anomaly **UPDATE** Options

[whiterabbit]

I've been browsing this site for awhile, as I restore my '75 914. I'm mostly done, just working on finishing touches and some drivability issues. You guys have been a huge help but the details of my current issue has me stumped. Below is a summary of the issue:

1-With key OUT of the ignition the charging light is "ON" (IMG:style_emoticons/default/WTF.gif)
2- Key in on position, the charging light turns "OFF", oil light turns "ON"
3- Engine Running, charging light is "OFF"
4- Engine running, voltage regulator plugged in, voltage at battery reads 12.4 volts (not charging).
5- Engine running, voltage regulator unplugged & jumper between D+/DF voltage at battery reads 12.6-12.8 volts (still not really charging).
6-Occasionally, ignition key needs to be cycled several times before the starter is triggered to start the car (probably unrelated?)
7-Charging light turns "OFF" when alternator plug (specifically DF connection) is disconnected from relay board.

Background info: New alternator 100 miles ago, belt tight, newer voltage regulator, new alternator wiring harness, newer ignition switch, transmission to trunk floor ground strap clean and tight. 20 miles ago, the charging system was working as it should.

My theory: Alternator failure! But I don't want to throw parts at the situation if there are other clues in points 1-7 above.

[Spoke]

1-With key OUT of the ignition the charging light is "ON" (IMG:style_emoticons/default/WTF.gif)
2- Key in on position, the charging light turns "OFF"...

This is really weird and exactly opposite of what you would expect. In this diagram, the GEN light is powered by fuse F9. F9 is switched from the battery (not shown in the diagram).

One way the GEN light would be ON with the key off and OFF with the key on is if one of the 3 diodes connected to B+ of the alternator has died and shorted out.

You can test this by removing the cable from the alternator to the relay board and measuring the voltage on the cable D+ wire. If it's close to the battery voltage, it is likely that one of the diodes has died and the alternator needs replacing.

Did you do anything to the electrical system after installing and getting the new alternator running? Did you disconnect the battery with the engine running?