HELP PLEASE! Fuel Gauge stuck @ 3.

[Ericram]

I know it's been beaten down to death by now but I apparently can't figure it out. I have a 71 c10 with 350/350. The gas gauge, sending unit, and printed circuit board are all brand new.

With the ignition ON and the wire from Fuel/Fuse panel to a ground(my chassis) the gauge still reads past full at 3.

I'm using a spare piece of 16g wire that I had, is that too big/small of a wire to test the gauge with?

Does there need to be some type of wires connected to the post on back of the gauge or is the printed circuit supposed to take care of that?

I have been riding with a gas can in my bed in case I get stranded and that's getting pretty old! Any help would be greatly appreciated. Thanks guys.