I do have 2016 GLC, and Merc dealer was told that i can add Apple CarPlay on my 2016 GLC, and it will be around $450. ($300 for parts, and $150 for labor cost).
Never heard of that being possible before!.
2017 GLC AMG43 premium plus, night pack, leather, intel lights, 360 camera, side steps. = sadly gone
Now GLE450 Premium plus, Selenite, Black/White Nappa leather, Tech plus pack, Driving assistance pack, Tow pack, Off road pack, 22 inch wheels.