Voltage Regulator problem

That wire from the starter relay should lead down the firewall and to the neutral safety switch on the transmission. The connector for the VR should be right there somewhere otherwise someone chopped it off. "It appears" that the two twisted together may well be the VR wires. Blue should be switched 12V to the VR and green goes to the disconnected field on the alternator. See if you can find the other end of the green if that is what that is, there, "twisted".

There is only one so called "run" wire coming from the key, through the bulkhead, into the engine bay. BE CAREFUL it is NOT FUSED. That wire splits off to feed loads under the hood, the ignition system, the VR, one alternator field, the choke, and any smog equipment "may not be present"