I didn't know how i miss this thread, But the swap is much harder that you make it seem sure it will bolt in,it the same chassis
. the main problem is wiring. I can think of plenty wiring schematics on mated this motor in an e46 that are not EVEN DOCUMENTED by BMW.
And NO its not similar to M54. It totally different rewiring of fuses, adding new wires to different modules, coding,programming etc. Try it let us know your outcome.