I got home and did some more troubleshooting.
Things I know for sure: Selector switch checks good (New). Pump relay checks good. Transfer valve checks good (New Pollack 65 psi).
LH Tank is known 1/4 full, RH Tank is known FULL. The gauge shows 1/4 full when the tank selector switch is in LH or RH position (makes sense for the LHS, but not for the RHS).
Troubleshooting: I disconnected the plug to the RH fuel pump/sender. The gauge stayed at 1/4 full with the tank selector in LH or RH position. The truck would start and run in the LH position (pump/gauge checks good), but would not start or run in the RH position (makes sense, pump not connected).
Then, I disconnected the plug to the LH pump/sender. The gauge went to the 3:00 position with the tank selector in LH or RH position (makes sense for the LHS, but not for the RHS). The truck would start and run in the RH position (pump is working), but would not start or run in the LH position (makes sense, pump not connected).
Possible problem: Sensor ground on RH tank? Hatzie, over to you.....
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