Hi
I have a Bedford and a Land Rover Dormobile, the front seats are completely different the land Rover has a double bench on the passenger side and a single seat on the drivers side these are fixed to a seat box where on the Bedford they are single seats,if you were to use Bedford seats you would have to drill thru the tubes of the Bedford seat frames and fix these to normal series Land Rover seat sliders,if you did this you would be only able to use the seats in single bed formation as the front seats would not move,in fact you may have to have adjustable seat sliders on the passenger seat so the passenger seat meets the rear when in the lie down position.
There may also be a difference in the height of the seats between the Bedford and the Land Rover,although the rear seats seem much the same, if i get a chance I will compare the height sizes of the rear seats
Regards
Malcolm