I believe that the G2 caliper paint is brush on. With the cash that you’ve invested into your calipers, I personally would never consider brush on paint. I would lightly sand, primer (also acts as a fill agent), paint, then clear. All those products can be found specifically designed for brake calipers. Good luck!
VHT makes spray on caliper paint, get the prime, color and clear: VHT Caliper Paint -- High Heat Coatings
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