About this 3D model
Based off of julienM's work. Simply kludged space for an LM8UU bearing. In the process I had to widen the rod slots as well to ensure no contact/friction along the model. Note: julienM also created an LM8UU version of this at the same time. You should test that one as well. http://www.thingiverse.com/thing:41986 The bearing holes and the rod shafts are purposely a little large to allow for a tiny bit of displacement to match your specific rod width. Use zip ties to ensure the bearings stay in place. Update: Added an instruction for drilling the mounting plate holes, as per JulienM's suggestion.