Removing connections from bulkhead!

The bulkhead terminals are termed "56 terminal" or "Packard 56". Used on 60-70's GM and Mopar, even later in Dodge motor-homes, also, in appliances. You can buy terminals on ebay, but not the plastic housings for our bulkheads. Wires are usually fine on the cabin side, so just remove and clean (file & contact cleaner). I think terminals are usually tin-plated brass, or sometimes pure brass.

If the engine side wires are brittle (common), might be best to rewire. That isn't hard, just tedious. Photo above was from my post where I rewired my engine bay (64 & 65 cars), using a relay/fuse box from a 95-99 Jeep, so I used smaller 20 awg ribbon cable since those simply actuate relays. You can buy non-adhesive vinyl tape to wrap new wires like the factory did. I used PVC sheath (ex. PVC-105, SPC Technology, can buy on ebay). Much easier to buy engine bay harnesses (lights and engine), if available for your unknown year and engine (Year One, etc).