1981 Chev C10 fuel issues

[cpach]

I can't switch tanks on my 1981 Chevy C10, she's stuck on the passenger tank. All fuses are good, swapped driver's tank and sender unit, checked ground and new selector switch, just won't change over or show fuel level in driver's tank. My selector valve on the frame doesn't make any sound when the switch is depressed, but neither does the spare unit I have. Any suggestions or help with this? Patches.