I'm in the process of installing one on mine, I have not come across a write up. But you can look up on google how to install CB radio or pa system on a car and the concept and set up is pretty much the same for every car. Your power source (whether you go through the fuse block, buy a fuse tap, run it to the battery, or pop the cigarette lighters out and tap into that wire) Then just find an area to mount the powerhorn or PA speaker and run the wire.
I had a PA in my 08. Had the speaker (quite large) mounted behind the front bumper in front of the driver side wheel. It was up out of the way, angled down in case any water splashed up, and I never had any problems with it through some really heavy storms and 70+ on the highway during them. I took the bumper cover off and mounted it with 2 bolts through the metal part of the bumper and then ran the wire up into the engine bay and through the firewall. I need to get one put in the new truck, I miss being able to yell at all the idiotic drivers out here.
kris you know there's a hole in the rear wall of the kc on the drivers side with a rubber grommet you can run that wire thru so you dont have a guido lookin wire comin out of your door hah, i ran my cb antenna wire thru it. if you feel around on the back of the cab on the outside you can feel the plug, just push it out, make a hole in it then pul back the carpet inside and locate the hole.
and i like the inner fender idea and behind the bumper i'll have to check that