How do you change power steering pump on 2002 Deville?

Do you need any special tools to remove the pulley? It looks like there is a hex head screw in the center of the pulley, if I remove that will the pulley just slide off?How do you change power steering pump on 2002 Deville?this proceedure is very high on the difficulty scale and requires special tool/s

If you don't have them, have someone who does do the job