Originally Posted by
Scrodzilla
If the dropouts are aluminum, you'll be ok. Just be sure to file them evenly or your wheel will be crooked.
To piggyback on this, only file the bottom side of the dropout to get the clearance you need. By just filing the bottom side (the one closer to the ground with the bike on its wheels) you can use the weight of the bike to let the wheel locate itself on a factory surface before tightening the axle nuts down.