Where's this little wire go?

I have an orange wire with 2 black stripes coming from the relay under the console. About a 12 Ga. wire. The power window schematic just shows it poking through the firewall. It doesn't show a termination. Anybody got a clue?
The schematic is from the assembly manual.
68, power windows.
Hatch

I can't speak directly to the '68, however, the later models had 3 wires on the power window relay. One goes to the window switches that supplies 12v to the motors. It would be on the common or 'wiper' contact of the relay. The other relay contact, the 'normally open' one, goes to the battery via the fuse block. The third wire is to supply 12v switched from the ignition to the coil of the relay. Ground for the relay coil comes from the mounting of the relay to chasis ground. The relay should close when the key is on.
Does that help?

A little more digging and I came up with a '73 drawing that showes a orn/blk wire going through the dash to a 30 amp circuit breaker. The other side of the breaker has a red wire heading off to the battery feed connection on the horn relay.

Thanks! I'll look for the breaker. There's one outboard of the master cylinder. It's kind of buried back in a hole.