After 8 years with my E53 (pre-facelift) it went to the next owner, so no longer in Switzerland but in Finland. I replaced it with an E91 330 xd and also want to do the LED thing for my angel eyes. All of the bulbs are 12 V, you need to look at your headlight cluster to be 100% certain.

In my case it is an H8. For an angel eye, you want 120 W (effective) per bulb (60 W is a a bit dim) and those who are made to be error code free. You also (angel eye) want the "stick" part of have the small LED's all round the stick (usually at 90 or 120 degrees depending on the factory that made them) rather than left / right.

__________________
2002 Euro X5 (E53) 3.0 diesel (M57)
5 speed manual with UUC short shifter.
Pre-xDrive NV125 transfer case (chain & gears).
Factory Xenon headlights, Spyder LED tail lights
Updated vortex crankcase breather.
Motorsport dead pedal, factory fire extinguisher, factory first aid kit, factory F&R mud flaps, factory PDC

Bilstein B6 shocks F&R
Redline oil has replaced "lifetime" fluids (F&R diff, manual transmission, transfer case and P/S).
Dimple magnetic drain plugs in all compartments.