A previous owner had the clutch pedal adjusted so that it was too close to the driver.  The clutch would disengage when the pedal reached about the same level as the brake pedal.

To move the pedal back to the same height as the brake and gas pedals, I followed these steps:

1. Remove the e-clip.  There is one on each end of the pin.  Take your pick.
2. Slide the pin out.  You may need to tap it out with a screw driver and mallet or similar.
3. Unscrew the clevis and locknut all the way off the pushrod.  Clean, degrease, and remove rust from the clevis, locknut, pin, and the treads on the pushrod.  Also clean the grime from the hole where the pin was.
4. Twist the locknut back onto the pushrod to the point where you want it.  In my case, it was all the way forward to lower the pedal as much as possible.
5. Twist the clevis back onto the pushrod until it is snug against the locknut.
6. Put a dab of grease on the pin and slide it back in.
7. Sit in the drivers seat to test the pedal height and disengagement point.  Readjust the lock nut and clevis, if needed.
8. Place the e-clip back on the the pin.

An unexpected benefit of lowering my clutch pedal is that it is now closer to a right angle with the pushrod which means I have more leverage with less effort needed to push the pedal.