Thanks folks, I wanted confirmation that the thermostat was difficult to replace on this car and it sounds like it really is.
One follow-up question: The problem with the car is that it randomly overheats. It doesn't seem to matter if it's city driving or highway driving. But the simple fix around the problem has always been to pull over, turn the car off, and then start it right back up (no waiting). The temperature always drops back down to normal within seconds. Without any real car knowledge, that sounds like a stuck thermostat. Can anyone confirm that before I go back and plunk down the $250+ to get it replaced. The dealership did not diagnose this as the problem, in fact, when I asked them about the overheating problem they checked the fans and coolant system and found no problems.