I just wanted to let everyone know it can be done. I done this a while ago.
It is installed under the passenger side under the back seat, not much room for anything else.
I made a cradle up for it to sit on as it needs to come up to give you enough room. I used the bolts at the back of the seat and drilled to holes in the front wall to hold the front of the cradle.
The air supply goes to a tank under the tray for both the air bag controls and a outlet for air supply. To lower the height of the compressor i used a 90 degree bend and then into braided hose to a check valve, this goes into a t piece. One for supply air, one to take air to the tank and also to use the ARB compressor fitting if needed.
Power comes from the second battery in the engine bay to a marine maxi fuse outlet, this also feeds both an anderson plug in front of the seat for when the small fridge is in the car, and another anderson plug in the tray for when the camper is on or fridge in the tray.