Hey guys,
I had my welder with me today, and I was going to make a gizmo to hold the water pump pulley in order to unscrew the fan clutch. I had the motor out, so it was easy to get a good look at it and realized that this would work great.
Just take a large open end wrench, I used a 7/8 but any wrench with a long enough handle to hit the crank pulley will do. Place it on the back side of the water pump pulley, over one of the protruding bolts that mount the pulley, and rotate the pulley until the wrench contacts the crank pulley. It gives you a super solid lock on the water pump pulley and you have both hands free to work with. Mine came off easily with nowhere near enough force applied to do any damage to the threads on the bolt, and it was locktited on.
Remember, reverse thread, or in this case righty loosey leftie tighty!
Good luck,
Mac.