First of all thanks for all the info in this post about this setup for the spd pedals.
How did you manage to match it? I have been triying to find a way to mount my m8000 on duo-shi and could not find it.
The axle is different and think do not match as easy nor the nut that fix the ball bearings, so bought the 520 that as stated in several post, is a bolt on and go.