I just noticed that the EPC shows two versions of the new Zero-G wheels that come with the Track Package. They have different offsets: WHEEL, 20X9.0J ET34, ZERO-G 1044242-00-A WHEEL, 20X9.0J ET40, ZERO-G, 1044243-00-A So it may be that each axle will come with a wheel with a different offset; though I don't know which would get the 6mm wider wheel placement with the ET34 wheel. It could be front for steering clearance or could be rear for looks. Either way, it looks like front/rear tire rotation won't be possible, or at least recommended. 6mm isn't a lot, so I'm surprised they would do this. It'll undoubtedly lead to some confusion since the tires are the same. Maybe the ET34 wheels are for Track Package, which is only for PUP cars, and the ET40 wheel will become available for purchase for all the other cars with the thicker brake rotor hubs? Anybody else have a guess?