I rebuilt rsee360's model in OpenSCAD to make it easier to resize it to fit larger wheels after buying the 7/8" Prime Line M-6153. You still need the carriage from the original design, and even at 3/4", it does not exactly match the original model, so it's probably best not to mix and match the wheel carriers. After building this, I've found the Prime Line wheels far too wobbly for my tastes. I like the overall design of this part, so I'm looking at getting wheels with proper bearings and modifying this design to fit those instead.