Have you considered simply taking the belt off of your chopper when you don't want to run it? Would that cause a problem? That would let you have your power when you needed it, and also let you keep your chopper...
there is a guy around here that grows corn under a circle (no, we dont grow much corn around these parts...gotta get on up toward Dalhart, TX for corn), and he had a combine with a straw spredder (whirly bird). The spreader didnt sling the stalks very much..