833 Transmission won't disengage at stop after 100 miles.

The input shaft looks like it got hot. I had an issue like your mentioned with a needle bearing cup input shaft bearing on my pickup. Truck would not go in first or reverse when the engine was idling because the input shaft was bound up on the input shaft bearing in the crank and when the clutch disc was disengaged the shaft kept turning with the crank.

I'd clean and polish that input shaft with a very fine sandpaper or crocus cloth to make it very smooth and polished up. Grease up that input shaft bushing. Do not use a lot of grease. Since it can spray out and foul up the disc. Bolt it back in and try it again.

As far as the Z bar goes. Probably find the one that fits correctly and install it. For such short miles on a relatively new clutch, that's certainly a lot of wear and heat checking on it. Do you drive it with a heavy foot on the clutch?