Normally I just bring along a Power Tank, but every so often I build an extended-range outback project (like Project Hatari! '71 CJ-6 shown) in which I want an unlimited supply of compressed air. For Hatari, I had an old Sun tank my old boss, Cole Quinnel, gave to me. I mounted it longitudinally under the passenger seat. That seems to be the best place to put an air tank on most CJ and Wrangler Jeeps.