92 cavalier 2.2 water pump

Need to replace the water pump on my daughters 1992, 2.2ohv cavalier.
Is this a difficult task? It is below the alternator. It looks like the alternator pully might get in the way. Can I get by just removing the alternator, or do I have to remove the whole bracket across the front of the engine??? Also, is all the nuts on this engine metric?