I ran 17x8" wheels with 225/45-17 tires, and had the same rubbing you described.
I learned not to use full lock when reversing.
However, lots of people use a mild lowering spring with this combination, and it works okay. I would recommend a 7 or 7.5" wheel, and watch how low you go. My car has the AMG "middle" suspension which has a very mild drop (just under an inch) and the rubbing wasn't any worse after installation.
But, the H&R springs have a rep for being VERY low. You may have to make further mods...
1998 C230 "Black Betty"