How much floor to you plan on replacing? The floors from the trucks were also used in the panel and suburban with modifications. The seat riser is different in all three, the suburban has a steel plate attached to the floor so that the jumper seat will sit flat. The after market replacement pieces will fit in all three. The entire floor that is available from many vendors will fit in all three, with a slight modification for use in a suburban and panel. The rear of the floor pan has been modified so that it will attach to the rear floor/plywood.
complete floor for pickup To fit the suburban and panel you must remove the section where the gas tank fits. You will have to remove the seat riser too.
There is one more style of panel, actually the first style of replacement panels that did not include the toe board, either left or right side.