The correct way is to run both big cables to the large post on one side, one from battery positive, the other to the main starter post. The opposite big post needs the small wire to the small post on the starter solenoid.
The incorrect way he had it before on the two big battery positive to one side of the large Ford solenoid post and the other to the big post cable to the main starter positive. This overheats the contacts inside the solenoid and makes them stick when the two large cables are on opposite sides of the Ford solenoid. Your car may not have a GM style relay like my brothers car has.
He did give me a diagram of it that I can scan and e-mail to you if you need it.
If you wire it the way you explain your only using the solenoid to activate the small wire which is then the same as what a mopar is already wired to do.
