1966 Dart Fuel Gauge??

the turn indicators are not wired to the fuel gauge. the turn indicators get their power via the same fuse, switch, etc.., that the front turn signals do. The fuel gauge gets its power from a voltage limiter. that limiter gets its power directly fro the ignition switch. Only fuse between the battery and limiter is fusible link.
The only thing the turn indicators and fuel gauge share is chassis ground.