Thanks Lou. Right now, I'm betting the generator brushes need replacing. Brushes are on page 55 of your operation manual. Not a difficult job -
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You can get new brushes from Moss Motors, or many other online sources. And you've probably got a "electrical starter and generator" repair shop within fifty miles of where you live.
When you say the ammeter did move a lot when you tried the lights on/off thing, it's probably ok, but may be wired for positive, not negative ground.
Hope this helps.
Tom M.