The truck floor has some shape to it for strength, and if it's like the AD models the seat riser welded to the floor is a big part of the strength too.
leaving as much of the original structure in place as possible is the better approach in my mind. If changing it be sure the new solution is sufficiently rigid.
Anyone have pictures and measurements of one installed in a truck? A late model AD seat is 53" wide I think, earlier are 52"..
I'm soon to buy, restore, or make a seat and want to consider one these as well, just looking at pictures on eBay they look promising..
Grigg