[Yosemite Sam]

I do agree with the guys about the pin being the right length... However

I am guessing that, in a round about way, you are telling us that you don't have your clutch issues resolved yet.

Since the transmission and creeper gears are not synchronized it is difficult (at best) to get the shifter to "lock in" at any given time while the tractor is setting still in the garage without the engine running, this issue is compounded when a creeper is added.

While gently pulling/pushing the shifter into its desired gear, rotate the drive shaft a few hundred times to get the gears lined up (more if the creeper is engaged). Once the gears are lined up the shifter should "pop" into gear (keep in mind that while doing this the creeper handle must be either all the way to the front of its slot or all the way to the back of the slot and not somewhere in the middle).

After the shifter is all the way in gear, raise ONE rear wheel off the ground and rotate the drive shaft several hundred more times to transfer motion to the rear wheel.

OR put the clutch back together and then answer these questions.

What happens when the tractor is on the ground, the creeper handle is pushed forward and you step on the clutch, start the engine, put the tranny in gear (I don't care what gear) and then let out on the clutch?

Then what happens when (tractor on the ground, with the engine running, tranny in neutral, clutch pedal pushed down) you pull the creeper lever back and HOLD IT THERE while putting the tranny in gear (I don't care what gear) then slowly let out on the clutch?