Hey Derek,
that’s really great how you solved the problem that with 65 mm mount, the milling motor does not clear the stepper, a solution similar to the taller stepper mounting blocks shown in this 3D-files package (see pic 2). It’s very nice to see you putting this basically obvious idea into practice! In this way, you benefit from a center of the milling motor that is as close as possible to the Z-rails/linear bearings. Where did you find the aluminium parts?
I notice that you also found a solution for the known cable connector issues: Hot-melt glue 
!