Another Adjustable Filament Spool Holder for 608 bearings

I liked the idea for the adjustable spool holder but wanted it to use 608 bearings and to be both easily adjustable and easily attached to the case I was building. I designed a new "soporte_eyes" that keeps the same spacing for attaching to the "parte_superior_graduable" but made sure it would fit 8mm (5/16") threaded rod. I also scaled the "maneta" part to 0.5 in the z axis and added two guides to it so that it would sit in the adjustable channel and could be loosened/tightened from underneat