Wiring starting motor selonoid?

[Newfiething]

I have 2 black wires and one red wire left to attach to starting motor selonoid but only have 2 terminals to attach to. I have a wiring diagram but can't see anything.I was wondering if anyone knew if one of the black wires don't get plugged into anything?

[edgy]

I can't remember since it's been a while. The large red wire has a lug on it and bolts to the large lug away from the starter motor. Whichever black one has 12V on it when the key is in the start position goes to the solenoid spade. The other may be for back up lights and just needs to go to a hot wire.

[Buckly]

I think there are two hot wires and one ground.
_________________
Cool runnins,
_______________________
Bucky