FUEL GUAGE PROBLEM

Hello Members. On my fuel guage 1966 Dart. The guage needle, in the car, goes from below empty to the empty bar on the guage, then stops. Following is what I have done.

1. New Dashboard Printed Circuit Board
2. New IVR4
3. New fuel sending unit.

1. Using the fuel sending unit outside of the car, with proper ground, and manually moving the float,
the dash fuel gauge shows empty to full as it should. This test was done both at the toe kick junction
and at the fuel tank sending unit.

2. The blue wire from the toe kick junction to the fuel tank sending unit ohms out showing no short to ground.

3. The IVR4 is new and the voltage shows as it should.

4. The Printed Circuit Board is new.

5. With the tank out of the car with the fuel sending unit installed along with a jumper ground attached and the. blue wire attached with a jumper wire to the fuel sending unit, I added water to the tank. With the water rising. in the tank, the fuel gauge guage rose from empty to full as it should.

6. I, then, emptied the water, dried the tank, and installed the tank with the fuel sending unit installed. I double checked for power at the fuel sending unit, checked for grounding, added an auxilliray ground, and added fuel. The 66 Dart has a fuel tank capacity of 18 gallons. I added eight gallons of fuel, and the fuel guage rose to the empty bar and stopped.

I do not know what else I can do to resolve the problem. Any other thoughts on this would be appreciated.
Thanks. Sgrip65