Ok, here is how to pull the tensioner, there is a bit of a trick to it, I did it a couple months ago to install a new thermostat, which by the way, if yours needs a new thermostat now would be the time.
First pull the belt off, you dont have to pull it all the way out, but tuck it down out of the way. Then if you look, when the pulley is in its free resting position, there is a bolt head underneath, in other words, the pulley is covering it up. Now you want to pull this one first, use the second bolt on top to hold everything together so it wont be moving around. If you have somebody to help you, it will be alot easier, get them to put a socket on the pulley bolt with a breaker and pull it all the way up, then you can get at the bolt underneath. Its a little cramped, but it will come out this way, just make sure whoever holds that tension real good. After you pull that bolt, let out the tension and then pull the bolt that you can see on top of the assembly housing. Thats it, then to install the new one, first put the covered up bolt in while its out of the truck, put it in its place, then hand thread it in as much as you can, then start the top one, go ahead and tighten it up to hold again, then get the socket/breaker and pull the pulley up agian and tighten up the bottom bolt, then the top again. This should help, its not that hard to do, as long as you remember the bottom bolt first. Hope this helps.
Oh and the new one comes pre loaded, you just install and then put the belt back on, it will tighten and align itself.
