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The late also has that nice oil channel carved in, which I was going to mention also. Can you machine down the new one you got to 23mm OD?
I've been trying to figure out how to hold the new bushing to reduce the o.d.
Those oil channels do look a little deep to take down the OD 1mm.. If you do decide to trim it down, I'd probably go with two aluminum cones with some sort of shaft/axle to hold it in the lathe. Being soft metal like that, it will probably shave off pretty quickly so the cones probably can be tightened enough without distorting the bushing. Something like this I think:lathe-axle-nut-cone>bushing<cone-nut-axleSounds complicated and dangerous
Maybe the best material would be the original? The updated gear with new bushing is quite available. I have several of them.