1971 Ford 3000 keeps getting stuck in 3rd gear

[Darrell Neumann]

I have a 1971 ford 3000 8 speed diesel the tractor was in very good condition until I started to have shifting problems . I bought a new shiftier and gasket from Steiner tractor. It worked for a couple of times cutting pasture with finish mower. The left gear stick started to twist when putting in 4th or 8th gear . Then it got stuck in 1st & 5th gear . I took back apart and used a mic to measure bottom of shiftier ball to compare with the shiftier assembly I took off. looked at forks and only thing that looked a little wore was front side of middle fork . I them prepped fork to beef up with welder and got it cleaned up and installed new gasket and wrestled plate back in all 3 pockets for both shiftier's and stationary pin for the neutral safety. Not a simple task peaking under and lining up all 3 and keeping gasket in place . It worked so the next day I bladed long path using shiftier may times working fine . No twist in 4th gear and every thing shifted fine when I was finished and taking blade off got stuck in stuck in 3 gear again . Inside of transmission case looks clean rails look good and fluid was changed when I installed new shiftier. any suggestions would be helpful thanks Darrell.