Fyi, I recently removed my gb system for a hei system on my '75 truck, so I have my gb system laying here.
The wiring description is correct, as noted by trevor.
The gb is grounded thru the black wire. The black wire just goes to any mounting screw for ground.
White wire, as described is correct, connect if you have a working decel module, or just leave it disconnected.
My gb system only had one power wire coming in, it was spliced (factory) into the black (coil + wire), in the harness between the gb & the coil +.
This wire connects to the red wire connection on the gb connector.
You will need to unwrap the wire bundle to see the splice.
I hope my description is clear.