Where do the wires go? Wiring a 904 transmission

One of the two is positive 12 volts from a fuse when the switch is on. I'm pretty sure that wire has or had a white tracer on it. The other of those 2 goes to the reverse lamp fixtures. Since that wire is routed through the rear lamp harness inside the car, both of these wires do pass through the firewall bulkhead connection. That's where the wiring diagrams are supposed to help. I don't know what else I can tell you