Does anyone have a shaky needle only when the guage shows that
the circuit is charging? No problems with the entire charging
circuit just a shaky needle!
I have the spare dash in my car right now and the ammeter is "loose". That
sounds like it describes your needle also. I think it happens to the old
gauges as the bearing wears a bit and the electrical connections start to
corrode (there are a lot of them in the positive battery side!).
I recommend replacing with a JC unit.