I installed new gauges in my 64 recently. Sport Comp gauges. The gas gauge didn't seem to work so I thought the sending unit was bad so, I replaced it this weekend. The fuel gauge dial only moves a fraction of an inch. I've checked the ground on the sending unit and the gauge. I even ran a new wire from the sending unit to the gauge just to check the wiring. Still nothing. I'm stumped. Any assistance or advice would be greatly appreciated.