Gas gauge always full (1968 Barracuda)

first thing I would do is disconnect the fuel sender at the tank. If at ign' switch on the fuel gauge needle remains at home, the short to ground is inside the sender. If the needle still races to full the sender signal is shorted elsewhere. Could be in the trunk or anywhere along left side of car. So pull the left kick panel and separate the rear harness connector. Ign' switch on again. If needle still races to full the short is somewhere between there and the gauge, maybe at the printed circuit board, maybe inside the gauge. Pull inst' panel. If circuit board pins, etc., seem fine, take a ohms meter to fuel gauge checking from post to post. Approx' readings expected , limiter is 50 ohms, gauge is 20 ohms, combined is 70 ohms. If the gauge winding is shorted to the beam, the expected 20 ohm reading will be wrong, 12 or less.