Ok, took a while to get the metal cut...
1/4" floor steel (hardened diamond plate) with U shaped supports underneath.
We attached using 1/8" angle iron down the entire length and at each end.
I need to figure out how to 'lock' it in place now so they can't move and I think we are golden.
Then it's on to cleaning it up and maybe bedliner.
Oh, that's dust on the steel, not rust.
Anyone think paint will hold up?