If you don't plan to replace the cam seals, then you won't have to remove the cam sprockets, which means you won't need to use a cam locking tool. Just make sure that BEFORE you remove the old belt you have the index marks on the sprockets aligned to their marks on the belt cover, and that you use a sharpie to mark the crankshaft sprocket's relationship to the crankcase. (There seems to be a lot of confusion about the crankshaft sprocket aligning marks so if you make your own mark before removing the old belt, and do so with the cam sprockets on their marks, then there will be no guessing when you are aligning the new belt.

Watch this video:

http://www.youtube.com/watch?v=IK_zH8g8Fow

It explains the procedure with the type of tensioner that you have.

If you have an impact wrench to loosen the crank pulley nut, then great, do as the video shows. But if you don't have one at your disposal, I've found that you can remove the narrow plastic guard that runs under the crank pulley (between the crank pulley and the engine block) and work the new belt in that way. (The old belt can be cut in half to make it easier to remove.) That guard is held in place with one 10mm? hex bolt at each end.

I have not yet replaced a water pump on one of these engines, but I noticed FCP had a video on Youtube to cover that also.