From a 1984 article from the Light Commercial Vehicle Association:
In 1950, "the floor boards of panel and canopy express models were changed to plywood construction. In the new construction a single panel of wood and five skid strips replaced thirteen floor boards and twelve skid strips. The new floor was positively sealed against dust leakage and the plywood made the floor 25 to 30% stronger than the former construction."
In all Advance-Design and New Design years (47-55), the suburban floors were made of single piece of plywood covered with ribbed linoleum (a tan color, I think, until it was changed to black linoleum in 1954).
Because it is difficult to obtain wide enough plywood to replace a piece that has been removed by cutting it out, Weeds, and others (with Suburbans), have replaced their wood with multiple pieces of plywood. You have to remove about 30 spot-welds in the side-edge angle-iron in order to remove the piece of plywood in one piece.
Tim
