If you can get the Jeep for about 3 hours and you are pretty handy/confident in your skills.... you can get the entire heater box assembly removed/reinstalled... I was very hesitant to start this job before I actually did it... but once started it's not as difficult as one may think... Unfortunately it was freezing out so I couldn't take the time to take pictures and actually write up a how to... but I wrote a basic "how I did it" afterwards...
http://www.lostjeeps.com/forum/phpBB3/viewtopic.php?f=3&t=72219