Green Diesel Engineering can do an ECO tune for $450 and program for the 5V glow plugs as well as disabling the EGR and FCV valves so you don't use them any more and the Jeep won't throw a Check Engine Light.
For Increased MPG, better stability, more HP, better economy, and the voltage flash, I would definitely recommend it.
Go to
http://www.lostjeeps.com/forum/phpBB3/viewforum.php?f=5 and read my post about "AT THE END OF MY ROPE" and you'll see I had some similar issues to your glow plugs, but I went with the 7V Etecnu's from Europe so I didn't have to flash the ECU.
If you need to change from 7v to 5v and you have a bad EGR, Dealer will charge you about $100 for the flash to 5v and the EGR will cost you $200 at Auto Zone, if it's not the FCV Valve, which will cost you $360 online or at the dealer (This is if you do it yourself). Dealer will want about $1000 to fix the EGR issue because they have to troubleshoot the EGR as well as the FCV and it's a LOT of work to get in there (trust me, did it myself)!
GDE is the way to go, ECO tune.
http://www.greendieselengineering.com or call them and talk to Keith.
Welcome!