The vehicles was set up to be a "cut through".  A "cut through" is where you cut a hole in the back of the truck's cab and the front of the bed so you can access the bed of the truck from inside the cab.  in our world, this allows us to put equipment (subs, amps) in the bed to conserve space in the cab.  However, this one was done using pond liner to join the two havles which created LOTS of problems that we had to fix.