I have been looking for a filament guide that would provide a 608 bearing for smooth rolling. I didn't find exactly what I was looking for, so I took the 2 reference projects and remixed them into this. I had to extend the clip to fit around my frame and had to cut and weld some other pieces.
You need one 608 skateboard bearing. It should press fit into the wheel. I printed with supports on just the main piece. None on the wheel or pin. I've uploaded all parts, even some from the referenced projects, to have all of the parts here.
Coex LLC PLA