Need help with seats in 51 truck

Just got 51 truck from my father in law hasn't run in 25 years have went thru all macanics new gas tank and lines new brakes overhauled motor went thru carb and generator new lights and put blinkers on it and new clutch only problem is no seats and no idea how they were set in there there's hinges on back of cab on a board looks ordinal did bottom seat hinge up or does it fold ahead and is the back rest stationary .

The seat frame included the frame for the seat bottom cushion and the back cushions as a one piece frame. There were hinges at the front of the tool box that allowed the seat to hinge forward all in one piece.

In my '48, the seat was a 2/3; 1/3 seating arrangement, but in later years the seat was a full bench, not split.