Ray, I found this image online of a 72' W-code car without AC. The orange wire looks like the one in my engine bay - it appears to run to the heater box. (for the fan motor, I think?) Anyhow, I don't believe I need it, my car has AC. Not sure why they put that in my harness? It's an American Autowire harness IIRC. Now I am just down to the one black wire I can't figure out.
