for my 2017 Mazda 6 Touring, I bought an Apple Carplay retrofit kit (made from China) at Amazon. I went to Mazda dealership for updated OS system to firmware V.74 about 4 hours installed and updated firmware. Labor cost $250 + tax in Florida, USA.
My retrofit kit won't work with my registered...
For my 2017.5 Mazda 6 Touring trim with A/T and I ordered parts at COX MAZDA, Florida plus tax and shipping price. Link address: https://parts.coxmazda.com/
#3 Cover wheel (GRT7-32-049D-02) $6.23
#6 Assembly cruise switch, w/paddle switch wire harness (B68K664M0A) $93.12 ... OR spaceman12...