To add some more info to this thread and help someone out in the future,I did test fit and buy a used e39 snow setup for my e46 m3. Because they are aftermarket snow tires and wheels,they were a square set and narrower than stock sizes. The hub ring can be 74.1 or 72.5 so a different ring may be required. These snow tires are 235/45/17 on the et 20 all around. The fronts sit a little inboard of the fender,but close to flush and have plenty of clearance lock to lock all the way around. Rear fitment of the 235's are fine concidering 275 summer tires had no fitment issues either.
I think an offset of 35,or a slightly narrower tire like a 225 for the front would be better to keep slush in the wheel well and not get kicked up the car as much but for the driving in bad weather that I do these Blizzak LM's will keep me out of the snow banks this season.
sent from my ATARI sc1224