MakerBot Print is our newest print-prepration software, which supports native CAD files and STL assemblies,
allows you to interact with all your printers via the Cloud, and many other exciting new features.
No, that's too big, the 3mm bore bearings are necessary to suit the M3 hardware and NEMA 11/14/17 form factor. Switching to 608s would require a major redesign of the idler fixing and arm hinge.
Is there any particular reason you want to use 608s?