So I took out the gauge cluster cover/lens because it was insanely discolored, and you couldn't even see the speedo any more. My drunk buddy not knowing this reached in and poked the fuel needle moving it to half a tank while the truck was off. The gas gauge now reads correctly but only if I tap next to it to get it to move? It will no longer move down to empty by itself as it should when motor's off, and just does not move freely. Is there anyway to calibrate it again? or am I just screwed and need a new fuel gauge?

 

There's no calibration and it's very delicate. You'll need to replace the gauge.

 

D3TZ-9280-A .. Fuel Gauge / Obsolete

Applications: 1973/74 F100/350 / 1975/76 Econoline / 1977 Econoline before serial number O80,001.

TISON MOTOR CO. in Estill SC has ONE = 803-625-2551.

KINSEL L/M in Beaumont TX has ONE = 800-816-2894.

GREEN SALES CO. in Cincinnati OH has TWO = 800-543-4959.

CARPENTER NOS OBSOLETE PARTS in Concord NC has FIVE = 800-476-9653.
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D3TZ-10880-A .. Instrument Cluster Lens-Clear Plastic / Reproduced

Applications: 1973/79 F100/350 / 1975/91 Econoline / 1978/79 Bronco.

Listed in Carpenter's 1967/79 truck repro parts catalog (2011 paper version) @ $25.00.

 

You might try a junkyard or eBay as well. Either way I'd say your buddy owes you a case of beer.

 

And the part......and buy new so it's more expensive.

 

I was detailing one of these and had slightly bent a needle; they are as mentioned very delicate. I think they are made out of thin aluminum; like soda can thin aluminum.

Anyways it wasnt working because part of the needle was dragging on the face of the gauge. A few minutes with a tooth pick and I got it straightened out but it could easily have broken as well. This is worth a shot but the j/y is a good back up plan as others have mentioned.