The backup lights have a single wire that goes to the front, usually through the connector behind the driver’s kickpanel. Going from memory I believe it routes to one terminal on the backup light switch. For 65, it’s mounted either on the lower steering column before the column goes into the engine compartment OR if you have a factory floor shift, the B/U switch is mounted by the floor shifter. The other terminal of the B/U switch is routed to the hot terminal on the wiper switch where it draws power!
