Hmm, that's an interesting idea. I would, of course, worry about wheel/tire clearance. There is a 20 mm difference in the tracks of the wagon and sedan in the front, 25mm in the rear (measured at the center of the wheel) and 35 mm difference at the outside of the wheel on the front. So depending on the wheel/tire combo you are running, you will need to roll the fenders.
It would be an interesting thing to try as there is a handling difference between the two vehicles due to the wider track of the sedan. though not that my amateur butt can feel it.!