The obvious answer is to splice in a new wire as close as possible to the connectors at each end. Before I do something irreversible, I want to verify my conclusions. My symptoms are no compressor OR condenser fan when engaging the AC button. However, I can engage either one by jumping terminals 1 and 2 on the respective relay sockets.

Following the service manual troubleshooting, they point to the pressure switch and indicate that I should have 12v between the No. 2 terminal of the A/C pressure switch 2P connector and body ground with the ignition switch ON. I do NOT get any voltage on either terminal of the 2P connector. However, I do get voltage between the No. 9 terminal of under-dash fuse/relay box connector F (12P) and body ground with the under-dash fuse/relay box connectors connected and the AC button OFF as directed. They state:
Is there battery voltage?
YES - Repair open in the wire between the under-dash fuse/relay box and the A/C pressure switch.

Anything else I should be looking at? A bad thermal protector should only affect the compressor. I suppose it is possible I could have 2 bad relays or bad thermal switch and bad condenser relay. The relays would be easy to verify. Neither would explain why I'm apparently missing 12v at the pressure switch though.