Have you read through the link I posted above? Look closely at the sleeve Gear bearing in the image that I marked up. Pay no attention to the detractors who had no idea what they were looking at. In that particular case the sleeve Gear bearing supplied, was a modified Bearing where they had enlarged the ID of the inner race. What that did was effectively reduce the radius. That radius is meant to clear the shoulder on the mating part, in this case the sleeve gear. I had a wobbling. Once I discovered that the shoulder was hung up due to the lack of radius, I used a different bearing. Had it been ground out of concentric also? Possibly so. Been in the metal trade my whole life I've seen all kinds of crazy things.
I am neither machinist nor engineer, I sometimes struggle to follow writeups here. That said I think I understand what you are detailing here.
I think the issue I am seeing exists in the bearing itself. The bearing in question came sealed in what looks to be original KSM packaging inside Andover Norton packaging.
With the bearing installed in the gearbox shell, and no sleeve gear inserted, I place a dial indicator against the face of the inner race. The same surface that the gearbox sprocket spacer 04.0131 will set against. If I try to move the inner race around to check for movement there is essentially none. Only with considerable force can I get a few ten thousandths to show on the dial indicator. So the bearing internals seem very tight, perhaps by design.
However, if I rotate the inner race there is a repeatable approximately 0.002" rise and fall shown on the dial indicator. This can be measured at both faces of the inner race, inside or outside the gearbox shell. I put a sharpie mark on the inner race so it can be seen that this is repeatable in the same place.
Insert the sleeve gear and place a dial indicator near the end of the sleeve gear, towards the clutch hub drive end. Rotate the sleeve gear and there is about 0.004" runout there, repeatable in relation to the inner race regardless of bearing to sleeve gear orientation.
With a mainshaft and inner gearbox cover installed there is increased drag between the mainshaft and sleeve gear at one point in the sleeve gear rotation. At the opposite point in sleeve gear rotation the mainshaft spins quite freely.
Keeping in mind this is not a race build, indeed I suspect I will do very little actual riding once I get this all back together I am tempted to go with it. But am curious if others think this is bad idea or is it making mountains out of a molehill?