Wow I am suprised to find this thread. This is exactly what I am going to tackle soon. However I wont be salvaging parts.
Looking to swap out a 2011 DCT E92 335is final drive for a 2011 DCT E92N M3 final drive
The M3 driveshaft, DCT transmission output flang, right and left output shafts are going to supliment the swap. I am going to also get the drive flang hubs just in case also.
This should be easier as the DCT transmission is the same