Peter-
Here's what ya do... Crawl under the front of the truck with a 13mm (if I remember correctly) wrench and look up to what will be now your right side and you'll see the tensioner pulley. You'll tighten the the bolt on the pulley and it will move up allowing you to have slack in the belt, you can then slide it off the pulley. Slowly let the tensioner back down, then you can remove the belt from the rest of the pulley's. Installation is in reverse order. An extra set of hands might be helpful when putting the new belt back on. Good luck!