For a more powerful and dependable electrical system I often convert to twelve volts . I like to buy batteries from Walmart . I can measure and pick the battery that will fit the original battery box . If there is a problem with fitting or anything else , Walmart will replace the battery with no question or problem here . It is a very easy conversion . Six volt batteries are getting harder to find and usually cost more . The biggest thing is the battery . I either use a three OHM coil or install a ballast resister and use the six volt coil . The unmodified generator and starter will work good on twelve volts . A good cut out will work on twelve volts but there will be no voltage regulation . I prefer to use the Fun Projects twelve volt voltage regulator . The Fun Projects twelve volt voltage regulates the charge similar to modern cars and looks just like the cut out . Of course the bulbs will need to be replaced with twelve volt bulbs . A resister will need to be used at the horn and electric windshield wiper motor where present . Other than the twelve volt battery that can be found most any where ,very few other parts will need replacement I run my roadster this way and LOVE it .