I have an inch spacer on the rear right now for the R58's I'm running and the 10.5's sat pretty much flush with the rear fender with the spacer, so I might just be leaving that on there. I actually ran into an issue with the front wheels, it seems the wheel hub opening on the 9.5 wheels is physically too small to allow the hub to pass through it. I checked the 10.5 and they were probably an inch or so wider and had no issue clearing the hub (hit the front strut though). Above all else I'm going to need a spacer to clear my brembos up front anyway so it'll be likely be a bit before I can get them on the car :/