I don't believe they were anodized since the tube side of the rim doesn't show anodizing and isn't painted either. I don't know if it's possible to anodize the 'outer' surface of the rim and not the 'inner', but think not.
It's possible the rim was etched to help the paint adhere, or at least prepped in some way because bare paint wouldn't have stuck as well as this. I haven't seen evidence of primer, and normally zinc chromate (yellow) is used for that. Maybe they got blasted with a fine powder to rough them up, I don't know. But however it was done they certainly did a good job.
Wanted: Dead, smashed, crashed or trashed gauges
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