Here is what you do.Get a new brass bearing from
Rancho transmissions($10),in calif. Dont know the number.Remove the circlip
from the clutch shaft arm. Drive  a chisel between the case and slave cyl
mount,to push the clutch shaft arm off.If it wont come off with modetrate
pressure,be prepared to saw the cos in two($18).EZ to do. get a new cos,of
course.I have done this 3 times. Twop came off like butgter.One took a ton
or two of dynamite.I finally removed the arm from the shaft just for saying
I did it. All was destroyed doing it.

Tap a thread in the new brass bearing. Get a bolt to screw into the brass
bearing.That will hold it.  There is a circlip on the inside that will
provide a bearing stop when the new bearing is driven in.Perhaps it has
come off? I think a new brass bearing can be installed with the trans still
installed.The passenger side bearing is brass and usually in good
shape,still.The driver side bearing,the one that takes the load, is
PLASTIC. If you want a AHD  clutch,get a brass bearing first.