I looked on realoem.com this morning and the radiator for my 6/04 production M56 is part number 17117513922 which is different than the 17119071519 shown in the list. It is also significantly more expensive at $456 from bmaparts.com. The ET, hoses, thermostat and pump are the same. I haven't checked all the other parts.
Any way to determie what the difference is b/w the radiators?