Well... the Mopar iPod kit install was successful on both my TJ and KJ! It works great!
The install on the TJ was much more work. For the box that goes between the stereo and the iPod, in the TJ there was no room for it around the stereo. The instructions had me remove the instrument panel and put the box in behind the panel! I had to take a lot of the dash covers off to do the install. Thankfully I had found someone's write up of how to remove a stock stereo. The "drawings" that come along with Mopar parts are very lacking in providing tips. For one, the stereo on the TJ had a nut behind it to make it harder to remove (or steal as the reason is). It would have been a lot harder to figure out where the nut was and how to get at it without the write up. Thank God for internet!
I did also use Benette's write up for pulling out the stereo on the KJ. It was much easier! My only issue was that I couldn't seem to locate where the antenna unplugged from the stereo. I wasn't able to reach far enough back and find the connector. Luckily I didn't have to pull out the stereo all the way, so no need to unhook the antenna. On the TJ, the antenna wire runs right behind the glove box and it was easy to unplug.
My KJ's stereo is RBP, btw.
This was a great mod, and the wife and I are very happy to have this. I highly recommend this install to all! It's easy to select playlists and different songs, and the titles display on the stereo (well at least the first eight characters do!). I have also purchased some audio books via iTunes that were too long to fit onto a CD, so this solves that problem!
As I wrote above, we've got an extra mini that can be left in the KJ, and I may buy an Nano to leave in the TJ. I love the massive gig storage on my iPod Video, but I don't want to leave it in there all the time.