While we are waiting for the poster to respond, I was thinking that if the signal wire on the tank level sensor, was removed and grounded, the fuel gauge should be showing fully empty. This would help isolate the problem between the gauge and level sensor. From the poster's first comments, the gauge is being bench tested and the gauge reads about 1/4 tank when float is fully down makes me think the problem is with the gauge or something wrong with the supply voltage. I may be wrong. Have to wait and see.
