I took a closer look, had to click the engine over a few times to get the belts in just the right position to check the printing, the accessory belt says "GM 24504257 SFR 6PK1539 EB" looks like this one might be original? the supercharger belt says "860K6 6PK2185 made in canada" I suspect this one is not original

My belt didn't break but it slipped off. One side, all the way around, was frayed. My 95 Series II has the motor mount in the middle of the belt, so it is no easy task to change it. (I was 10 hours from home but thankfully only minutes from the hotel when it slipped off. I too worried about overheating and valves getting crushed.) It turns out that my Belt Tensioner went bad. Looking back, my car had given me clues that I didn't realize at the time -- the small amount of fraying, the belt starting and stopping!!! The thing is my car has the "mother of all belt tensioners". It has a coolant line passing through it. So it is a more complicated part change. A GM mechanic once warned me that these things go bad around 140K. I was at 135K or so. I'm now at 262K! I also had my AC clutch go out 2 years ago. The belt and AC pulley kept spinning and made awful noises. I had little metal shavings around the pulley but at least it didn't lock up and interfere with my belt moving freely.

The pulley didn't break off. It has been awhile now, so I don't remember exactly anymore. But, yea, I believe it was the spring and/or parts related to the spring action. - Angela Bonner