You’ll want some rigidity in a bed platform. What I’ve got and would suggest is using 3/4” ply and cap it with some aluminum C channel on the front and rear edge, you can use some spray adhesive to wrap the panels with some sort of fabric to finish.
It sounds like you might want to make your platform out of a few more panels to be able to more easily move or remove them. Instead of one or two large panels, you can have one larger fixed one towards the rear that you leave in place and have 2 smaller panels up front that can be moved or maybe even 4 smaller panels.
'03 Ford E350 7.3L Diesel
(de)SMB'd Custom RB-50
Quigley 4X4 w/Deavers & Agile Offroad's R.I.P. package
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