89cutlass,

I am not sure that all 1947.5-1955.5 Suburban rear floors are the same. If your suburban floor is a single piece of plywood (as it is in 1954), it can only be removed (in one piece) in an upward direction. The sidewals below the floor curve inwards and prevent removal in a downwards direction.

You will have to remove the right-angled retainer (ledge) from one side of the interior. This is spot-welded directly aboove the floor (at least 28 spot welds). With the retainer removed from one side, the floor can be angled upwards and removed. I have never done this but have talked with two other people who have.

You say you want to go with a stronger wood - that plywood seems quite strong (if you have plywood).

Tim