Instrument cluster testing

Okay. I hooked it all up on the work bench. I used the 23 ohm resistor for half scale to check the gauge. It slowly went to full. Not good I assume. I then took and hooked up a sending unit to it and with the float down it still went slowly to full. When I moved the float manually it went to full faster. I then checked the voltage at the FS stud and the oil and temp stud and read 12 volts (should be 5)
? So i guess the VR in my fuel gauge is shot. The reason the po had aftermarket gauges in it. LOL can my fuel gauge be repaired?
Luke