Isn't it dependent on transmission? If memory serves the M5OD and A4LD are the same length (don't know about spline count and so forth, haven't paid attention to much 2WD stuff) but the 2.9L used like 4 transmissions over the years so it's more of a crap shoot on that engine. and after the A4LD stopped being used I haven't paid nearly as much attention... I could have sworn there were some interchangeable years but I could be thinking 4x4...
Don't want to confuse things, I'm open to learn...