I've been in this thread from the start so I know not to over tighten the case screws.
It binds just pinched together with my fingers.
I'm guessing the case has worn around the idler gear pin or the top shaft bearing mount.
I have a spares car so I'll rip that down and try that case. I've already taken a shock standoff, springs and a drive shaft off it so I may as well break it down completely now.