Well, this just happened to me. I was in a hurry to finish mowing so I could free up the Jubilee I've had for nearly 20 years for helping with hay starting tomorrow. Alas, I slipped going from 3rd to 2nd and got into 1st for a moment, but then the shifter locked up and will not move. I am unable to get the shift cover off as the shifter is locked into place, and of course the tractor won't run. I tried shifting the link I can see through the screw off fill cover, but that makes no difference. The motor continued running fine when this happened, as long as the clutch was in, but the tractor will not roll. I tried rocking the tractor and moving the shifter, but no success. We have 4 tractors on the farm and this one has been my favorite for the most variety of jobs, but it is just blocking the barn drive now. Any ideas?