These cars have headlight level sensors in the front and back suspension that when functioning correctly, automatically adjust your headlight level, even if you change the rake of the car with an upgrade.
The rear level sensor is easy to R&R incorrectly.
2007 328i ZSP. M3 suspension
: custom valved Bilstein shocks, Hyperco race springs, M3 lower control arms front and rear, M3 sway bars, and M3 subframe bushings. E46 front guide supports. Euro tail lights.