How do you replace the alternator on a 1991 Oldsmobile Cutlass Supreme 3.1L?

I have an 89 cutlass supreme 3.1 and it should be the same. Remove the belt from the alternator. Next, There are two bolts on top and one under it. The two bolts on top are both size 10 wrench or socket and the one on the bottom is 13. One of the bolts on top is located on the right hand side of the alternator if facing it from the passenger side fender. The other one on top is connected to a metal arm just to the right of the wire that plugs in at the top and to the left of the other bolt. Unplug the wire. The fun begins here. The easiest way I found to get the bottom bolt out was using a short ranchet with a swivel head, a short size 13 socket and lots of patience, because I was only able to get very small turns on it. There is probably an easier way but I was unable to find it. Once the bolt on the bottom is loose and you can pull it out, I had to move the metal arm out of the way, that you loosened earlier, to get the bolt out completely out. a little, have fun.

You can take the whole aluminum "plate" off rather than taking off the third, buried alternator mounting bolt. After you loosen and remove the belt take off the three nuts below the alternator that mount the mounting plate to the engine block. It will be easy to do and easier than chasing that buried bolt.