Erich, the German website is wrong. It cannot fit both. An 075 is good up to 9/92 and an 082 is for cars after that. (It is in my compatibility chart :-) ) They have different electrical plugs. BMWfans shows the A5S310Z KO as the replacement for the box in my old E34 VIN GA11907:
http://bmwfans.info/parts-catalog/E3...ssion_a5s310z/
That had an 075 box in it when it left the factory so I think that is the one you need. I'd suggest the KM may have been an 073 box except it is a bit strange if they put an older box in the car