Auto head-light level sensor

[malibudave]

I mentioned in a different topic that the plastic arm of my front right headlight level sensor has snapped, leading me to blind oncoming traffic. I reckon its a simple job to replace, however I had a sudden thought that once fitted, the system might need to be calibrated? Does anyone know whether it is just case of fitting and "off you go", or will I have to take it to BMW to get it calibrated?

Any help is much appreciated!