Pete Haburt came over, and we:
o verified the mystery wire (power to harness)
o installed the carbs (with some clever work – rotating the brake master cylinder in place).

o installed the fuel line
Thanks, Pete!
I got some things done in the interior, and Brad arrived. We tested the power, and found all worked except the headlamps. Brad traced the problem to the dash switch – we got it working, but will replace the switch. We tested the fuel line – no leaks.
Electrics -done, well. almost.
We also did some wiring routing, and verified the fuel lines.