When I was a teenager, I had a 54 Chevy Wagon with a a rebuilt 235. It was hard to start with a 6 volt battery, so I installed a dual volt battery. I haven't seen them discussed here. It is like 2 6 volt batteries in one with a fancy switch on top. For starting it put out 12 volts and then ran the car on 6. Starting on 12 was never a problem for any lights, fuses, or anything.
Chris
