It's a lot of work, but you will LOVE it. It's great offroad too because you can open/close the windows whatever and the truck tries to stay at the same temperature. None of that fussing with the heater where you alternately bake and freeze, lol. It fusses with itself..
Edit: By the way -- LOVE that nav system and the graphic you put on it. I use an onboard laptop with satellite photo map data for offroad nav, but I'd love to be able to do it with something like yours. It looks perfect in the dash the way it fits and all.