If the outside door handles turn down, then you have a 1947-1951 door (those doors would fit/work on a 47-55 cab; however, you would need to use the 47-51 door catch/striker).
If you have a vent widow on a door with turn-down handles, it is a 1951 door.
Vent window and push-button door-handles are on 1952-1955 doors.
Your truck might be a 52-53, if you have vent windows and push-button handles on the doors (and if those are the original doors) and a split windshield with flat glass (a 54/55 has a single-piece curved windshield).
Do you have an ID plate on the driver's door post or on the glove box door (I am sure Spanky asked you this, if you have been discussing your COE with him)?
