Phewwww. So the short molex lead off the flyback that leads to the isolation transformer was just chilling, hanging off the back of the monitor., not connected to anything. But I couldn't find a corresponding molex connector in the cab. But I did see a 2-wire cable with female pins that looked to be unsheathed from a molex coming off the isolation transformer on the floor. For kicks, I plugged them into the isolation transformer molex lead coming off the monitor and flipped the switch. I immediately heard a fuzzy sound of electricity filling the vacuum tube. And viola! I got video again, although v-hold was going nuts.
Question is now, are these two wires polarized?