A couple of quick thoughts on the problem. Has one or more of the motor mounts or trans mounts sagged or otherwise deteriorated? Is there excess slop in the pedal arm bushings causing a wobble side to side or similar movement to hang up the clutch pedal? Is the clutch fork pivot ball inside the bellhousing worn or the dimple in the fork where the ball seats about to blow through from wear?
To me it sounds like a wear problem at some point so what I mentioned is at least a place to start.
Mike
