391 owners may be able to shed some light on the fuel feed system on the 60 gallon configuration. Reviewing the IPC it details a fuel shutoff valve located above the left rear seat and actuated by a push pull cable, the lever is above the pilot. I suppose this is because the fuel return from the pump is feeding back into the right tank. Being there is only 1 fuel on lever so fuel balance can be managed. I did not find this configuration when I disassembled it for repair. Are there some out there configured this way? It does show this same configuration for 60 gallon or 120 gallon capacity. Also has anyone ever seen the aircraft configured with the aux. 25 gallon fuel bag located in the rear? Thanks for any input.