If 2mm is a concern, then you may want to reconsider running tires with rounder shoulder, or stretch tires a bit by downsizing the width 10cm. For example, going from 225-45-17 to 215-45-17I'm running 17x8 +40 and the front looks to be close to even with the top of the fender opening (maybe a little room to spare). At +38 - you'll only be another +2mm out so it may be OK. I'll try to post a pic or two this weekend from the top of the car and along the side so you can be the judge.