It looks like the roof cover is going to be built into the cross-bar that separates the front glass piece that opens and the rear glass piece. So there will be two covers. One that pulls forward from the cross-bar and one that pulls back from the cross-bar. We still don't know what the mechanism will be for keeping the cover attached to the roof when it's pulled out. Will there be a track of some kind? will it be stiff enough that it won't need a track? Unknown.