Prints with no supports. The lengts are designed in a way that the 300 mm nood will fit perfectly except for the red chanel but there is a hidden compartment where you can hide the exces nood. Its a 3 part design that clips into place. You need to get creative to hide the wiring well. I suggest lots of hotglue.
For more information you can check out this model from Addafruit.
The author remixed this model.