Replace the cover with a spacer of similar stack height, that will allow you to look at the bearing while you rock the steerer around so you can see exactly what is moving when it shouldn't.
Thanks. I'll do that and report back within a month or so given the pace of my projects at the moment.
@drøn started
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Replace the cover with a spacer of similar stack height, that will allow you to look at the bearing while you rock the steerer around so you can see exactly what is moving when it shouldn't.