Did you figure things out?
(Been a couple months)
Sounds to me like you have two bad gauges.
If the fuel gauge is functioning properly, your regulator must be good. Ensure your jumper wire on the back of the gauges is installed. Verify your wiring connections and condition of the b/h connector connections. As long as the wiring is correct and you ground the temp or oil wire, the gauge should peg. If they don't, the bi-metallic strip heater in the gauge must be burnt open.