Originally Posted by
badamsjr
Could not really tell from the pics, but for an external BB, you may have a problem. Road cranks are sized for 68mm BB shell, and MTB BB shell is normally 73mm wide. I ran into this trying to use a DA triple on a MTB frame. You might consider having your LBS face the BB shell to 68mm width (if you want to make it PERMANENT). I ended up using a different crank.
Not always. Not even usually. Most MTBs are 68mm, 73mm is less common, but it certainly is something to check for.
5mm is a heck of a lot of material to remove with a facing mill.