How to change a power steering pump on a 89 ford sable?

i know to take the 3 bolts off and then take belt from around the pulley and i dont know what and why i need a puller to get a bracket or something i was told in placeHow to change a power steering pump on a 89 ford sable?pully will need to be removed from shaft so that the pump will clear the bracket. Be careful not to damage the hoses as they are a pain to replace...