The generator fuel pickup is located 1/4 up from the bottom of the fuel tank. It does not use the gauge. Once the fuel level drops below the pickup it dies. My generator runs fine with the gauge on E.
The scangauge does not read the fuel level at all. It just tells you total gallons used. Just reset it after a fill up and it will tell you, with pretty good accuracy, how much fuel the injectors have sprayed into the engine. It will not record generator fuel use but that is pretty minimal.
2014 Seneca 37FS