I recently installed some, I originally had a 1.5 gallon tank, but promptly changed to a 5 gallen tank. I paid right at $300.00 on ebay for mine. One thing to remember, the kit does not come with enough parts to get the job done correctly. I also installed some quick release fittings to the tank so Now I have onboard air for airing up tires or anything else you could use air for. I used a couple of relay's in the wiring, now I have a switch so the horns train horns blow when I press the factory horn button, or I flip a switch and only the facory horns work. I mounted my horns on a plate under the passenger side of the bed near the rear window, they sit above and to the side of the drive shaft/exhaust pipe, kinda a bitch to mount by yourself, but doable (wear safety glasses). The compressor and air tank is mounted in my toolbox. If I get a chance i'll post pics later.
