Oh no, you can't copy my storage setup. It's patent pending number: 6,976,329,352.
You can see what I did. It's was a fit-as-I-went-along thing. I added the wedge shape to hold the floor jack in place. What you can't see are the 3" holes I cut in the right side 1x6 piece that lets the rear HVAC air out. There are duct openings in the trim there.
The only thing I might have done different is a split lid or the like. As it is, I have to unload everything off the false floor before opening up the full sized lid. I have recently redone my setup, by adding a Rubbermaid bin box. Bottled water, emergency food including MRE's, extra oil, antifreeze, etc. etc. etc. are all in that box. The box got heavy and is held in place by straps hooked to the back of the rear seat, but it can be set out on the ground when needed. It also doubles as a seat to sit on.
I left the original rear storage in place. With the lid turned upright, there's room there for handy grab things like a small shovel, the original jack, set of under-the-tire mats, road flares, a trucker's (reflective) triangle, and other items. Nothing has to get unloaded to open that up. Also, that original jack storage stuff houses HVAC duct work between the two sides of the back area.
I guess my problem is I pack too much crap to fit it all under the floor. There is a lot of room there, but what with an X-Jack, large ARB air compressor, recovery gear, floor jack, jumper cables, tire repair kit, tools, etc., there's no room left for the rest. I like to be set up well enough to live comfortably for three days should I get stranded somewhere. If I should ever blindly follow my GPS into a snowy road to oblivion like the tragic thing that happened in Oregon a few years ago, at least I'll be walking out clothed in a parka with electric heated socks and gloves, a rabbit hat, and snow boots instead of tennis shoes and a windbreaker. I'll be eating beef jerky along the way too.
It does work good now with the bin box idea. I can get into it easy for most often needed stuff, and if it comes out to get to the storage underneath, it's serious. (The Jeep is frame buried, a tire needs pumped up and/or repaired, etc.)
Note that I built mine flush with the original jack storage lid to make a flat floor. It could just as easily be built higher, making for a larger storage underneath the lid. Or lose the OEM jack storage and go all the way back to the hatch door. I came ''this close'' to doing that in the first place.