So in the back of my mind, I was finding it hard to believe that the generator itself had failed, as I have seen how unreliable the Voltage Regulators are on these cars in the past.
Tony 64 above said exactly what I would have told someone else too.
Then when browsing around on youtube I found this video:
In short, he suggests connecting a jumper between the battery and the field terminal of the VR to bypass it and send full power to the field. If the generator starts charging, then the generator is not the problem - the VR is...
With the engine running, I did this and got a big spark - then disconnected the jumper.
I tried it again and got NO spark. I left the jumper connected and looked inside the car - NO GEN LIGHT!
I disconnected the jumper - and the light stayed off.
Shut the car off - turned the key to On and the GEN light came back on. Started the car, and it shut off immediately.
Now I'm getting 14.5 V at the battery when its running.
So to summarize - I am not really sure why it started working again. I did do the polarization procedure before, and apparently either didnt do it right, or didnt use a large enough gauge wire, or - I did do it right and something else was wrong. Perhaps the big spark I saw when I first energized the field was the new VR waking up and blowing the soot off of whatever was preventing it from working.
The cause of the problem will remain a mystery. But for now - everything is working as it should again.
I will go buy another VR just to have yet another backup...