1. Begin by turning the printer off and unplugging it from the wall.  Remove the back panel.  See the grey cable coming from the print head.  Take a picture of how it is zip-tied for re-assembly reference.  Cut the zip ties and unplug the wires from the mainboard.  Leave the detached grey cable in the back area of the machine there.  Do not pull it through the middle panel at this point.
  2. Remove the two belts from the two idler pullies on the far left.  Then, pull the belts off of everywhere else so that they hang freely forward of the print head.
  3. With the wires and belts detached, bring the gantry to the far back of the printer and use your m4 allen wrench to separate the black y brackets.  Unscrew both pullies and the catch the two nuts and lower y bracket as it comes apart.
  4. Swing the bars down and slide the hotend with attached belts off.  Pull the grey wire through the middle panel.