Not sure exactly what you mean with such a brief question however if you refer to the headlight detail like has been posted about recently by Birchall it's not an 'off the shelf' item and requires a lot of fettling. You also need to source a set of splittable headlights from early model A2 as they were changed to a bonded housing around 2002.
Most of the tech savvy guys are at Audis in the Park today so you may not get a specific response. Steve ( Birchall) is always very helpful so when time permits if you explain what you want to achieve he may be able to assist with the source of parts etc.
edit: just noticed this is your first post. Welcome to A2OC