So I ended up using the earlier model transfer case from a salvage yard to avoid any compatibility issues. 100,000 miles later I had to replace it again (it had 50K on it). Can't complain...my '04 X3 now has 275,000 miles on it with the original 2.5 liter engine! I just picked up an '06 X3 3.0 with 100K as a new project car.