Okay - I've posted this elsewhere, but it might be worth its' own thread, as the alfa-specific xenon ballasts become harder to find
Removing the bumper, and headlamp unit to replace the ballast have been covered enough times - however one thing that's not covered is fixing it when the self-leveling and initialisation aim the wrong direction (up, not down!)
Remove the lamp and open the rear of the xenon side (three screws)
Remove the igniter connector on the rear of the bulb and look for this plug :
Pop the plug - and observe the order of the wires
These control the stepper motor in the lamp unit. A simple, interesting feature of stepper motors is that you only have to swap one pair to reverse the direction, in this case the pairs are red/brown and blue/black.
Using a jeweler's screwdriver, pop the cover on the plug
Push gently on the tabs for the wires you want to swap, and pull them out - you'll need to do it twice per wire as it 'snags' ... once out, simply pop them into the reversed positions
(In this case I swapped black and blue around)
Reassembly is, in the tradition of the Haynes bibles, the reverse of disassembly.
Power on, and marvel as your headlamp now levels in the correct direction