Alternator 1991 Cherokee?
It's an old Mopar/AMC retread - go to any local junkyard - they're full of them.
Not sure if 1991 and 1989 is same Not sure if the alternator is under your right front seat on a 1989 model, but it is on 1991. You need to remove the seat and the top under the seat to get proper access. When that is done, it is easy removal of the alternator. You will see that the alternator is self explainable.