An 8 volt battery is a solution to a nonexistent problem. Get the cable connections clean and tight, and use at least #0 AWG welder cable for hot and ground leads instead of conventional battery cable. In order for an 8V battery to work, the voltage regulator must be set to 9.5 volts or more. Headlights, points, charging system components, and other electrical parts fail quickly from the over voltage.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!