I recently(this last weekend) installed a new recirc door in my 06. I bought the complete door kit from heatertreater.net
It took me 10 minutes to get my truck into the shop, another 10 minutes to drink two beers, 5 minutes to walk back down the hill to get the doors and another beer, and 10 minutes to install the door and have everything put back up.
Only tools I used were a phillips screwdriver and a pair of dykes.
THANK YOU heatertreater.....
The mix door and recirculation door are two different doors. The recirculation door is a lot easier and less expensive to fix.