1. Loosen the set screws on the coupling.
  2. Remove the four screws through the block at the bottom.
  3. Remove the two screws through the block at the top.
  4. Lift the bed with the attached threaded z rod up and off of the motor shaft.
  5. Holding the bed up, seat the coupling onto the motor shaft and tighten the motor shaft set screw.
  6. Lower the end of the threaded z rod down into the coupling.
  7. Tighten the other coupling set screw and put the screws back through the blocks.