FYI - My car was suffering from a stiff clutch pedal. I just got it back together yesterday, here’s what I learned:
The problem turned out to be the release fork bearings and a badly scored shaft. The shaft had 1mm deep vertical bearing grooves in it.
Also, the Sachs clutch kit comes with the stiffer 911 pressure plate, which I sent back.
I got away with just replacing the disc, fork bearings, shaft, and repacking the TO bearing. If if wasn’t so easy to access, I would have replaced more parts.
Tip:
Insert the driveshaft all the way into the disc plate and make sure the locking clamp bolt will engage before you tighten everything down. You need a little bit of free play in order get the shaft into the end bearing. The driveshaft has a 360 degree groove for the clamping bolt.