John, there is also a trick to getting them out with ease. Turn your key as if starting the boat, and you will get the starter to hit (just do it for one "fire"). This will push the impeller (in the housing) a fraction of a turn. When you are doing this (might take a couple of times) it will at one point recoil back a little and the fins will not be pushed down as hard. This will take most of the pressure off of the impeller making it much easier to get out. Then like Darin said, a pliers or a vise grip will do the rest. Also, you should be changing the seal on the housing with every swap.
Hope this helps, John@waterskis.com www.waterskis.com
(Message edited by mnwakerider on July 27, 2009)