The PTO shaft should pull out after removing the 4 bolts in the flange. The book says do not force or pry, it should slide out easily. If it will not slide out it may have a twist or burr on the spline end that may require the tractor to be split. Not a big project. I had the same problem with my 52 TO30. When I got the tractor split, One rap with a hammer and the shaft slide right out. I replaced the entire shaft 1-3/8", fully assembled with bearing and seal. (availible on this site ~$120) Glad I did it!