It is possible, if the sender side of the guage is grounded, it will read empty all the time. You can do this quick test to help isolate the problem. Disconnect the sender wire at the tank, if the guage now swings to full, guage is good, trouble is in the sender itself. While you're looking at the tank, make sure the sender wire is actually hooked to the sender terminal at the tank, and not the ground terminal.
If disconnecting the sender wire at the tank has no effect on the guage, make sure the sender post on the guage isn't grounded or that the sender wire itself isn't pinched under something and grounded, and make sure "hot" side of the guage is actually getting voltage when you turn the key on (you can check this with a trouble light or a voltmeter).
