Well I used Joe's idea and put 12V to the motors, they definitely do spin in opposite directions but the end result is a forward movement of the chassis! Good news. I believe this is because the motors are very close together and the drive axles are on opposite sides of each motor's vertical drive gear.
I started removing the unused wires from the 40 pin connector. Still more to go.
Well will have to do more in a week. Have commitments for a while.