Maybe the 06 is a little different. I put the 5mm on the rear and went for a drive. All seemed good until I hit a monster of a bump and heard that tire digging into the fender sound. The way I drive and the roads here made the decision to remove the spacers easy. I have -1º negative camber in the rear. With more negative camber you have more room.

Les

I see the difference now, I'm an inch lower in the back.