Last summer, I bought a 1066 open station. I have NO clue how that tractor might relate with yours so pardon me if I'm off base here...
Turns out, I had the sloppy shifter issue. To fix it, I had to remove the shift box on the right side of tractor, replace the parts in there (after beating the heck through the TA rod/hole to remove the cylinder those parts rode upon)
Decided to pull the lid off the shift area and in my specific case, I was missing the spring that was between the two levers, one detent wheel and the detent "knobs" looked to be a bit worn down. My (what I think was my park/lock shift fork also had a serious "dimple" in it where the rod would hang, keeping me locked in low/neutral and unable to go into high gear)
I decided to fix it all and though it's still not dialed in (I avoid working out in the cold since I CAN avoid working in the cold) but, I got a lot of the slop out of the shifters too by tightening up the little 90 degree elbow pieces that link the lever to the rods.
Still have some slop in there but just a little, especially compared to what it was.
Again, don't know if that might help but for me.... just some rudimentary tools and I got it done. The hardest part was removing the cylinder that the shift arms ride on and then....pounding back the replacement.
Oh, and INSIDE that cylinder is a bushing that I either had to purchase to replace (I think it was $40) or, use a (if I recall) 10mm socket that PERFECTLY fit the inside diameter of the cylinder and just tapped out the bushing.