You should have negative ground, Dale. I don't have a 1956 to look at, but in the 1952, the right side is positive and that wire heads off to the starter solenoid and another wire may be connected to that terminal which heads to the horn. The other side is negative and it will tie to your ignition switch and the B terminal on your voltage regulator. You're wiring your wipers and radio to your ignition switch, yes?
