How do you change the serpentine belt?

OK. I am the one doing the work Chuckles car. We finally broke down and rented a TOOL for it. The leverage of the long tool worked to loosen the tension. But NOW that we can get the belt OFF. There are engine mounts in the way of getting the OLD belt off and the NEW belt on. Is there a preferred method to THAT? I see two bolts holding the engine in place from the top on some sort of rubber bushing, and it looks like that would be the ideal spot but the weight of the engine is just too much to create a big enough gap to get the belts thru. We tried jacking the engine up a lil but felt we were only lifting the car. And we tried using a giant crowbar to PRY it up (cause it looked like thats what someone had done before based on BENDS in the metal) and even THAT wasn't enough!

We replaced the belt because of wear and tear. Now as we drive it the serpentine belt comes off while driving.

Looking at my engine I have two belts, the one large belt connecting the Waterpump and Power Steering pumps and the smaller belt connecting from the waterpump to the alternator. Both belts squeal starting from the large belt that then stops transfering over smaller serpentine belt. The belts are new and I think they've just stretched a bit(under 9 months old) I've checked with a straight ruler and everything is aligned nicely. I've figured out how to tighten the alternators belt but the large waterpump/power steering belt I can't figure out. From examining the setup it looks as if the Powersteering pump needs to be adjusted to make the belt tight. I found one bolt that was loose that appears to be where it's tightened to hold it in the new position but I can't make the pump move in any direction. Is their another bolt that needs to be loosened? Their is one bolt almost opposite the adjusting bolt but it's hidden behind the pulley and I can't see how it would be used to tighten the pump as the belt and pulley would need to be removed to gain access there isn't even holes through the pulley to access it. A picture would be great. The car is a 1991 pontiac grand am LE 2.5L

Thanks, However, not sure why this is he official picture. My car is like it says 1991 pontiac grand am 2.5l LE however it uses 3 seperate belts and has no tensioner pulley. One large belt wraps around the crankshaft and travels up to the power steering and then over to the water pump. A second belt attaches also to the crankshaft and travels over to the A/C. A third belt attaches also to the waterpump and travels up to the alternator. None of the 3 belts have tensioner pulley. All the belts are adjusted by moving the A.C pump, the power steering pump and the alternator pumps to make their respective belts tighter/looser. However I am unable to make any of the respective devices move. I must be not seeing a bolt or something.

Absolutly positive it's a 1991. Manual must be messed becasue even Lordco gave me the correct belts for the car.