'65 Dart wiring diagram for air conditioned car?

I'm doing some troubleshooting right now and I've run into a roadblock...

My air conditioned '65 Dart has an intermittently working heater fan. I have the dash partially torn apart, and have determined that I have no power going to the fan switch. I DO have power at the vacuum switch that controls the heat/defrost. Unfortunately, the wiring diagrams I own/can find online don't show anything about a Dart with air conditioning. Therefore, I have no idea where to start tracing this wire back.

So, if you have an idea of where I could find a schematic for the dash wiring for an air conditioned Dart, I'd REALLY appreciate it. Thanks!