air conditioning wiring help

I'm working on a 1969 chevelle malibu. someone has cut some of the wiring for the ac system. I need to find a schematic or if someone can answer these questions.
does this system use an ac relay?
if not i'm guessing that the 12v comes directly from climate control to the temperature reastat, then to the compressor.
should this system use a diode at the connector for the compressor?

The relay is on the core support. By the voltage regulator. Driver side.
If you have a fax, I can fax you the schematics.