When you have the sending unit connected to the dash gauge, what does it
read and how  much fuel is in the tank in comparison?

If the tank is empty, pull the sending unit, connect it to a multi meter
(Ohms resistance) and see if the resistance varies smoothly thru it's
operating range.

If so, check to make sure the arm isn't bent. At rest, in the lowest
position, the float should be close to even with the pickup tube filter.

If it works smoothly, and the arm is correctly positioned, then the problem
is in your wiring or the voltage regulator on the dash.

Budd

The gauge reads empty and there is about half a tank.

Where is the voltage regulator on the dash. Also when I check for
voltage going to the sending unit the test light has a steady blink,
is that normal.

I will have to drop the tank down to remove the sending unit to
perform the test with the ohms meter.

Thanks.  Warren