Drivers side window roller good or bad?

[Big Dawg1]

My driver's side window does not appear to be tracking properly and barely seals against the T-Top trim.
I put a scope into my Z's tack and looked at the Z32 top window roller. See picture.
Although dirty from 33 years of use, it appears to be intact and in the track. The only thing that looks different than a new one (see Z1's picture of a replacement) is the area circled and pointed to.
Is this normal or is the shaft somehow unscrewing from the roller part?
I've tried adjusting the window inwards but that hasn't helped.
Any ideas are appreciated.
BG