I just looked at the EPC to determine the ICV part numbers which are as follows:

380 and 500 USA: 0001411225
380 Euro: 0001411325
500 Euro: 0001411425
420 and 560 Euro and USA: 0001411625

IIRC the USA 380/500 ICV has a notch cut in the slide which will admit more air for a given pulse rate than the EURO ICV. The big block ICV's have a larger cross section and greater opening depth when at rest. It would seem that MB's goal was by tailoring the ICV sizes for each engine the idle computer would operate in the same range regardless of application. Please confirm this for yourself since it has been some time since I had to deal with this issue. Also I just checked prices on 380 USA and Euro valves and the prices are through the roof (discontinued/dealer only apparently). The other difference in the systems was the earlier 380/500's used the 16 deg. C oil temperature sensor to tell the computer the engine was cold and thus needed a higher idle rate and the later systems used a water temperature sensor. Mark