I just wanted to pop in and mention that I'm finalizing the design for the 15" RPF1 center caps, and will be teaming up with Marc over at CarbonMiata to produce them very soon.
14" versions will be coming soon, after I do some local inspection and test fitting.
Below is a 'low res' 3d printed example of the center cap being test-fitted on my Mazda 2. It's more of a 24-sided polygon than a circle, but the finished product will be a perfect circle.
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