If you check the buyers guide there are a couople of photo's showing how a bent chassis affects the way the wheel sits within the arch , but dont get too worried. The tolerances used in the assembly of c5's was never that great from new
As long as you have the correct number of bearings (yes I've seen 3 bearing cages forced in..) with everything properly postioned and correctly set up then I wouldn't worry if the wheel stands a little proud. My c5 known as "Moneypit" is the same.
Post some piccies if you're still concerned and we can all pass judgement