You can just take of the pump part. It's awkward but doable. The pulley has to be done with the proper puller and press tool or you can damage the pump. I think autozone has the pulley tools in their loaner stuff. If you take both pumps back to the store some places will change it for you free or for a small fee. Look at how the pulley is installed now... it has to be on the same way on the new pump or you'll eat belts from having the pulleys out of line.
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The only thing George Orwell got wrong was the year...
The Ogre's Fiero Cave (It's also at the top of every forum page...)