OK, Im back a few months later with an update, a dead battery, and more questions...
1 - the intermittent symptoms described in my first post (abs/srs lights, weak idle, no tach) came and went but never stayed for more than a few minutes.
2 - a few weeks back I started using my car battery to power a 12v fuel pump, I left the car running while I did this.
3 - yesterday, while driving home from the mall, the abs/srs lights came on, power started to dim on headlights, windows, radio, and the idle was really weak, and the battery ran dead while I limped home.

I guess this isnt the OVP now? Did the 12v pump kill the voltage regulator?
I have a volt meter, what tests should I perform to track down the exact problem?

thanks for reading.