Would it be possible to source the parts from a 3 wire O2 sensor equipped car and retrofit to an earlier 1 wire car?

 

Should be easy. You could fit an ignition switched relay to power the heaters and plug in the sensor wire to the existing harness as normal.

 

If anyone can snap some pics of the factory wiring, I would appreciate it.

wondering if its an entirely different harness or if this could be easily added to what I have in the car.

 

The original installation, circa 1987, took 12v "+" from the brown/slate wire of the fuel pump relay.
Ground was a simple black wire to....I can't remember. But a known good ground point, likely on the engine itself somewhere

Cheers
DD

 

If some could take a picture of factory heated sensor wiring, Id appreciate it.

i assume they are powered by one of the relays on the rad support.

my rad support.