Pulled the flywheel on my Wr426 this weekend. When putting it back together, I was tightening the nut down to 47 ft/lbs when either the nut or shaft stripped. I can't get it back off to check which or both? I tried to back it out with vice grips while pulling but can't get it. Wondering if anybody has had this happen? If so what did it take to get it off/fixed? Would it be safe to run it as is?