If you're running an 8-volt battery and trying to charge it with a 6-volt generator and regulator, you're doomed to failure. There's simply no way to make it work. The regulator must be adjusted to 9.5 volts, which overloads the generator, burns out headlights and other bulbs, and requires a ballast resistor to keep the ignition from burning out the points. Either go back to a good 6-volt battery, or do the conversion to 12 volts. I grew up around a shop where we did top-quality electrical work in the 50's, and early 60's, and Dad would never attempt to make an 8-volt system work, even when a local battery manufacturer offered to pay him to set up the electrical system for every customer who bought one of their 8-volt batteries. It just can't be done!
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!