Some more design work on the tilting rear wheels

March Madness gave me a bit of time to design the tilting rear wheels assembly (while listening to some games).  I found some commercially sold square carbon fiber tube that can work for building the left, center and right channels.  Additionally, I have found fittings that I can bolt my  rear wheels (from my existing handcycle) into. And finally, I have found the correct carbon fiber tube that will accommodate those fittings.  The 3D drawings are updated to detail the correct size of pipes, bearings, and square tubes.