Deepseaskateboard said:
USB in arm rest, and bluetooth for calls yeah.
If you already have Bluetooth and USB then no you don't need to wire all of that in. Presumably you'll have a MULF in the boot (behind the panel to the left og the ski hatch). So in that case all you really need is the headunit, the screen, the iDrive controller and the USB to go in the glovebox (all of that is included in the link I posted, along with a lot of wiring you don't currently need). So with what you have and what I've just listed you'll also need a GPS receiver and the radio cage (as it's different from the standard headunit). This will give you sat-nav, radio, CD, USB music, AUX input and bluetooth for calls.
It would still require some coding though and the sat-nav may still require an FSC code to work (or an emulator adaptor which is probably cheaper!)