PrintrBot Simple Y-Axis Belt Conversion - Modified Bearing Mount

This is a modification of one of the parts from iamjonlawrence's brilliant Y-axis conversion (http://www.thingiverse.com/thing:180146) to toothed belt for the PrintrBot Simple. He had a problem that, when he really tightened the belt, the bearing pillars weren't up to the strain.
He's designing a part for the tops of the bearings to help, but I thought there was a bit too much hollow space in the pillars. So, I just filled them in a bit.
This design is untested, and will take longer screws