For BMW, it's probably just a few hundred dollars over and above what's already in the car. But for a retrofit, I predict it would be the one of the highest-dollar, lowest return upgrades in the history of the M2 - and perhaps BMW.
The pricing isn't available yet, but here are the part nos., so someone can let us know.
Left: 63117469787
Right: 63117469788
Don't forget the double-button turn signal stalk and all the hidden bits and pieces too...
