My third and (hopefully) final iteration is still under construction. I had to wire it up today prematurely due to the bad weather down here and me and fiancee needing to both have 4wd to get to work.
It will include everything my second system included, with a few additions and relocations. The batteries were moved to the floorboards, with an area in between the batteries that will house the intelligent solenoid as well as a closed accessory fuse block... and will have hooks to hang plastic bags for trash. I can to this design by observation, since that is always where we want to thove trash anyways. The back seat takes up more room then you would think, and I can now fit 90% of what was in my tool slide under the hatch where the rear seat used to be. This frees up space in the back for more kitchen related gear. Where the backrest of the rear seat used to be, there will be three 20L Scepter water containers, which will be secured with quick fist clamps. The fridge box has integrated holes for ventilation. Additional accessories, such as the power inverter, HAM radio, and stereo amplifier will be in the same locations as before, underneath shelves that will be installed as soon as the weather warms up.
A custom size foam pad with dual removable covers will go over the hatch so the dogs can ride comfortably, and a free floating pad will be placed over the battery boxes to keep claws from causing unsighly damage.
I am really excited about this setup, as it will give me much more storage space while allowing me to lower my truck's center of gravity.
It's nice having a friend who is a professional carpenter. If you like this system, contact me and I'm sure I'll be able to talk him into making more of them, now that the design is figured out.
Without further adieu, the pics: