So I've been reading many of the threads and it is my understanding that for the basic model factory stereo/CD, there is no accessory power and that a aftermarket stereo won't work without a special module. Is it possible to bypass the acc. switched power, the battery power, and the ground of the factory harness with separate wires? I would still be using a wire harness to connect to the factory plug to the new stereo for the speakers, I just wouldn't be attaching any of the power wires from the factory harness, instead the wires would be wired straight to the aftermarket stereo. Would this work?

 

I think that would work as well. There aren't a lot of good options for going through the firewall for your power, however. I just installed a separate subwoofer and amp for my son this past weekend. I ended up drilling a hole up high on the transmission tunnel in the right side footwell. I installed a grommet and the power cable fit through tightly.

After my initial posts, I bought a Alpine headunit off of one of the JK members. It came with a PAC adapter already attached. He'd used it for several months in his Wrangler. The adapter is probably the best way to go. It makes the install very simple and everything works the way it should. You simply solder the wires from the headunit to the wires from the PAC and then plug the other side into the factory harness. We didn't add an amp for the 4 main speakers so I used the factory speaker wire.

The sound quality was better than stock with the Alpine and 4 replacement speakers (Pioneer 3-ways in the dash and Infinity 3-ways in the soundbar). But it really came alive with the sub. We used a Rockford-Fosgate PL3 shallow mount (sub and box came together) with a JL 250 watt amp. It provides more than enough power for the overrated Rockford sub.