For reasons that I'm not sure I can fully justify, I've installed TWO ARB Twin compressors in my new JLUR. Excuses: it gives me some redundancy in case one of them fails; it halves the time to fill 4 tires (my wife does two while I do the other two); it's just cool and I'm the first on my block!
As usual, the installation was more difficult than I expected. Mostly due to my fumble fingers and my bad back.
Each compressor is mounted under the rear seat to a small piece of 1/4" plywood with the ARB hardware which in turn is sandwiched between the seat legs and the floor using the stock bolts. I used plywood instead of metal because I wanted some thermal insulation (those compressors get really hot!) and because I'm no good at metal working
When the seats are folded they hit the compressors and stop about 1/2 way down. I didn't like that it was pressing on the output coupling so I glued a small piece of wood on top of the compressor so that the seat hits it first.
For two compressors I ran 4 wires from the battery to the compressors' location. I was lucky to find a hole in the floor of the Jeep underneath the carpet in almost a perfect spot right next to one of the bolts that holds the outside front leg of the passenger side back seat. The hole was plugged with a rubber stopper which I popped out and drilled holes for the wires to pass thru. Of course, the ARB wiring harness is too short so I spliced it to a 12' piece of #6 wire from Home Depot. I decided to wire the ARB switch directly to the battery instead of to the ignition as ARB recommends so that 1) I can use the compressor with the engine off and 2) so I didn't have to run yet another wire. The switch is glued to the plywood near the back out of the way but still easy to reach.
I doubt I'll ever need to fold the seats completely down but if I do, I can remove the compressors easily by removing the two seat bolts and undoing the electrical connector.
Now all I need is to get my 37s on the Jeep and hit the trails...