Some rings similar to those are very easy to change as they have only a few (three?) tabs on the back to secure them to the gauge housing.
Most Pantera gauges, however, are fully crimped all around and are a HUGE pain to remove the rings from without damaging the rings. I speak of the '71 gauges that I have done. Maybe the later ones are different, but I don't think so.
Note that those rings lack the detail the Pantera gauges have — although they are similar in shape to the all-black Mangusta gauge trim rings.
Mark
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