Wanted to share a picture of my rebuilt distributor. Housing was vapor blasted to restore it to its original aluminum finish. I then polished the machined surfaces in a lathe. Let me know your feedback.
Edit: sharing photos from a couple different lighting conditions to give a better feel for its actual look.
Cleaned (not the machined) appears to be a bit brighter than original but maybe the lighting and angle or it may also just dull with time and exposure. Most of the time the freshly cast surface didn't look monotone so not sure how to go about cleaning the surface, removing years of neglect and producing the same look. Maybe the wheel cleaner trick might help or work but would need a test unit to try it out on. Get to get the garage done so I can get back to experimenting in the evenings
The other thing that should be noted is that your efforts do not seem to show damage from the cleaning and how little, if at all, it changed the flashing and sharp edges of it, we often see associated with other media
Just for comparison here are some originals
This one appears to have had the machined surfaces dull with age and slight (well stored) exposure to air
Close up of some of the surfaces. Machined surfaces are more pronounced on this one
Fresh out of the sealed box. Boxed in 68/69 up close