A complete retrofit will take some wiring and reflash of the LCM. It is a pretty intensive job, and if you don't have headlight washers, the Xenon retrofit requires the vehicle to have those installed too.

If you can settle for manual adjusting the headlights, just installing xenon headlamps and ballasts will be fine. It will be much more cost effective but you won't have autoleveling with your xenon which can be a safety hazard when your car is loaded in the rear.

Thanks MINIz guy,
My X has the auto leveling standard beams and I simply want to swap these out for a set of xenon (with the built in ballasts etc) from another X5 of the same year as mine...

Is it just a swap? Or is there other wiring required... (yep, good point about the washers...)