About this 3D model

You want V2 of this part. It is better. http://www.thingiverse.com/thing:49192 This is a simplistic Y rod mount to free up Y travel space and use the aluminum extrusions as the clamping reference. The downside of this design is that it is a pain to get the screws tightened. I would recommend hex head screws since those are easy to tighten from the side. I used pan head screws and pliers to tighten them. These were printed with a 0.35mm nozzle and 0.25mm layer height.