Clutch Fork

Hi
My transmission has started to grind when up shifting and down shifting, all gears, and double clutching doesn't help.
I have tried adjusting the clutch according to the book. When I adjusted the pivot point on the clutch pedal to the
measurements in the manual I found that I could not adjust the rod that goes into the back of the master cylinder.
It was too short. I readjusted the pivot point according to the length of the rod. Now there is 1/8 inch of play in the
pedal like it says in the manual but the 2 inches from the clutch pedal to the pivot point is way off.
I suppose none of this makes much difference as long as when the clutch pedal is depressed the clutch is fully
disengaged. I have taken the inspection cover over the gearbox off and when the clutch pedal is depressed there is
plenty of fork movement. My question is. What is the measurement of the clutch fork travel in a standard gearbox
that is adjusted properly?

Thanks
Mike