I decided to try and make the new aftermarket reproduction distributor drive pinion gear work.
It barely went into the AH case, nor would it go into the AR case or this new one so it is obviously a tad too large.
I used emory cloth to hone the top and bottom areas, essentially polishing them. While they will have grease and oil on them, not even that was going to make it turn smoothly in the case so polishing and slight material removal will have to do!
I smoothed out the bore as well, getting progressively finer though the main area and down farther inside the case.
While I think I probably need a minute or two more of sanding and polishing, I at least can get it to turn when installed, something it would never do in any of the cases. So… some progress.