I made mine into a proper bushing setup, no roller bearings but a plain bearing. So much better than having to tension the damn bolt. Got a bunch of people asking if I was going to start making it, but like you found, there's a bit of variation in the shifters and things pretty much had to be one off. Wasn't worth it at the time. I think the variations actually come from the base tube on the shifter being slightly warped/out of round from the welding which causes my bushing/your bearing to be deformed slightly. I was thinking it'd be worth reaming/boring the shifter would be the way to go, but never really spent any more time digging.
Good work!
-Dan
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