The bigger problem is that you have a 6-volt generator. And, a 6-volt generator will never be able to charge an 8-volt battery. So, your idea will work for about two hours.

I have a restored 1947 Plymouth Business Coupe. That was the same year I, too, came off the “assembly line.” The Plymouth has a 6-volt battery, and the starter motor turns over slowly. Can I safely ...