reading somewhere previously, the base model IS the wide body setup from what GM is saying. I'd expect some much wider rubber on the road (although the Michelin PSS base tires are supposed to be fantastic). More carbon fiber, perhaps a more aggressive spoiler/front splitter setup? The full on Z51 package with gen 3 MRC/full width spoiler/20" wheels is pretty balls to the wall right now, any further and you'd be a pure track car scenarios I'd think. Of course, they could lighten it up some more and throw another 200 bhp or so into the mix just to make it totally nuts......