On our first Muni ride last seaon, we had really crappy snow condions the firs day or so, and we had to change slides on at least 3 or 4 sleds. Everybody just tipped their sleds on one side, removed the screws, used a long screwdriver to start the back of the slide through a track window, grabbed the track, gave it a pull, and voilia'! It was easy enough to have to do trailside.
Helpfull hint. Spray the inside of the new slide with WD or something, and use an old piece of slide material to cover the end of the new one as you tap it back into place. Don't forget to put that screw back in, making sure its fully seated. One rider lost a new set of slides due to a screw that wasn't tightened.