Just finished bolting down the false floor's frame. It's in pretty solid, now.
I installed a riv-nut in each side, at the tailgate end of the frame. You'll see where in another picture.
A spacer at each bolt location makes up for the carpet thickness.
All four bolts installed; two pictured here. The bolts and riv-nuts on the front end of the frame, close to the rear seats, were already there for the original tie downs. The riv-nuts I installed are under the sides of the frame, close to the tailgate.
This view shows one extension, and how it rests on the extra frame member, taking the load off the hinges. You can see some useable storage space in the gap between the seat and floor.
This picture shows how the headrest will fold flat when the front seat is moved forward, giving plenty of room to lay out an air mattress.
The jack and tools are accessible without having to open the storage box; handy if you get a flat when the cargo floor is loaded.
This picture shows the jack compartment covered.
The last task related to this project is to figure out a nice locking system for it.