Instead of paying the $40-$50 for the "impeller tool", I took one of the flat metal pieces that they sell with a decent size u-bolt and notched out a spot just the size of the impeller. I used my Dremel to cut the notch.
Any flat metal piece will do....
Just cut a notch in it so that you can "hook" the back of the impeller the same way the expensive "impeller puler" tool does. Once hooked, just pliers or a vice grip to get a really good grip on your home made impeller tool. Presto! It will slide right out.
Mine is snug up against the engineroom bulkhead (great design... not), so I had to gouge out a little bit of insulation
there to get my took in place.
If you need more clarification and don't understand... let me know. I'd be happy to go into more detail. Basically, just make a square ended hook that fits in behind the impeller the exact same way the expensive tool does.