Technical Help with identifying gas tank

Does anyone know what this gas tank might fit? I am usually pretty good at identifying parts but this one has me stumped. It looks like it might be an under the seat tank because of the two posts on the top front. What confuses me is the location of the gas fill. It seams very close to the tank for a seat cushion to be on top of it. The sending unit is mounted from the bottom. The measurements are 44½” long by 19¼” wide. Thank you in advance for any assistance.


Bottom

 

It looks very much like one from a 1937 Ford truck, (not a pickup.)

 

I agree it is a truck tank, has the neck been modified? Bob

 

Defiantly an under seat tank with those dowels sticking up to locate the seat.