I just had the water pump go on my 2003 ZTS, and not wanting to blow $400-500 on a shop doing it, I did what any self-respecting fellow would do: googled it, and found this thread. Fantastic resource.
Took me and my dad almost 3 hrs this afternoon. Did not remove the motor mount (well, it never came off the car, it was loosened), nor the AC pump. Extracting the pump was exactly as described (the manufacturing engineer who said that was enough clearance between the motor and frame needs a kick in the junk.. just sayin'), but reinstallation was considerably harder. We wound up using a prybar between the (stuck to the motor) motor mount and the fender to wiggle the engine around a little. Seems the replacement pump was *slightly* larger than the OEM (maybe 1/16th of an inch) and it took an act of Congress to get it back in the cavity.
Another thread had a diagram of the serpentine belt (thank god!) but it took my dad (a retired automotive engineer and guy who's been working on cars for 60 years) and me (former helicopter mechanic and tech guy) about 20 minutes of head scratching and google-ing (mostly headscratching) to figure out the belt tensioner. My dad was looking for the 1/2" square drive hole for the long breaker bar. I wound up getting up under the car and looking at the tensioner for a minute before I realized how it worked. The 12 or 14mm open end on the pulley bolt was the trick, but only after I stuck another wrench on the end of that for some leverage. My tensioner was was stiff. When the belt goes eventually, its only going to take me 15 minutes to slap a new one on. Sweeet....
Thanks so much for the photos and clear description. This thread was instrumental in helping me save a couple hundred dollars that I didn't have to start with.