SUCCESS!!! Thanks for all the input. After thinking about the impact wrench suggestion I thought I would try one thing before I used pneumatics. I took my 18volt cordless drill and just tightened the chuck down on the spinner adapter much like you would do with a drill bit in the chuck. I then hung on to the prop and let rip with the drill. Worked like a champ! That drill had ample torque to break the nut free and the chuck had no problem hanging on to the spinner adaptor/prop nut. Needless to say I am very happy. Again thanks to all for the suggestions, it really got my mind going in the right direction.

Ken