I have just bought a 1982 F150 fleetside shortbed 4x4 with dual gas tanks. Unfortunately, the bed is rusted out. I found a flareside bed with a single gas door that I want to replace it with. Do I need to get the gas tank from the flareside truck as well or will the front tank neck fit onto the flareside bed? Also, does anyone know the fuel capacity of the dual tanks and the single tank?