I have a Post Hole Digger made by King Kutter with a slip clutch and the Quicktach bit assembly for my 2016 1025r. I used it to build two decks this summer. Worked just fine. Problem is, I can't for the life of me get the bit off the gear box. I've chained a long break up bar (6 ft) to try and unwind it, and a few other things I could thing of. It's just screwed itself on so tight from using it, I don't know what to do. Any suggestions on how to unscrew the bit?