All fill and drain plugs are 14mm allen - access to transfer case and rear diff outer cambers is very limited. So I had cut 1" and 2" pieces from large a 14mm allen key and it worked out great.

Front Diff:
BMW Final Gear Oil C-SAF-XO SAE 75W-90 - P/N 07512293972
Fluid Capacity approx. 750ml - Fill until it drains from fill plug.

Transfer Case:
BMW DTF1 or S-Tec Transfer Case Fluid (From FCPEuro)
Fluid Capacity approx. 850ml - Fill until it drains from fill plug.

Rear Diff:
Outer Chambers - BMW SAF CARBON MOD GEAR OIL - SAE 75W-85 - P/N 83120445832
Middle Chamber: BMW Final Gear Oil C-SAF-XO SAE 75W-90 - P/N 07512293972

Fluid Capacity:
Left Chamber: 540ml - Fill until it drains from fill plug.
Right Chamber: 580ml - Fill until it drains from fill plug.
Middle Chamber: 970ml - Only add 970ml.