This is always the best advice. Anything needed to run your winch, straps, shackle, etc. All where it can be grabbed even if you have flopped.
@LFGdigital have you heard of OZTech? Burro Utility Slide - Milwaukee Packout™ Compatible Truck Bed Slide - https://oz-tech.com/products/burro-milwaukee-packout%E2%84%A2-compatible-truck-bed-slide
He makes custom packout mounts and other mounts for similar style boxes. Hes started making slides, I had asked him about the idea of making a slide for the 80 and he was down, I just haven't decided I really want to go that direction. Very nice guy. Met him at an event in Arkansas.
"I also didn't want to add a bunch of weight.."
... Until I saw this..
Now people think I'm unofficially a contractor!
almost exactly what I imagined, only a quarter as tall unless I'm doing the first FJ80 box truck conversion and pulling out a personal loan to afford all that Milwaukee red plastic.
As I recall; between the wheel arches 3rd row seat forward bolts, 40". Cut in half, 20", -1" per frame rail, 18". minus .75" for each draw slide rail ~16.5"
If he makes a pack-out plate section that is no wider than 16.5" and no longer than 40" it would fit perfectly behind the rear seats with space to spare between the tail gate. that's factoring the 2nd row seat angle.
If not; it would be easy to make something on CAD and have it laser cut via send-cut-send..