Hy bigBob, welcome, when you say the cable starts to smoke, do you mean the whole length of the cable, or just the ends? Six volt starter cables are supposed to be twice as large as twelve volt cables, and since six volt stuff has not been used since the mid fifties, true six volt cables are getting hard to find. As for the ground strap, yes the factory had a braided ground strap going from the battery to the frame, and from the frame to the engine. So re-establish a good large ground from the battery to the engine, and make sure you have a six volt sized hot cable to the starter, hope that helps.
