I guess you don't have the automatic tensioner for your S/C... don't assume that the stealer will get the tension right for the S/C. Most of the techs will set it by hand to "tight enough" - this either will be too much and put too much load on the nose bearings, or not enough tension which will slip and ruin a belt pretty quick (while you're at it, you may want to make sure you always have a spare belt anyway).

Most dealers have specials running for the timing belt. It should be about $250 or so. I did mine at 195k and it was easy, all except the timing tensioner. It is supposed to take a special tool to compress and it took alot of "creativity" to figure out how to do it w/ my own tools. The new belt is very tight to put on even with the tensioner fully compressed.

There's a tech writeup of a belt change here.