Coming Home lights

That looks like a good retrofit. I would really like that function mine.

Are you going to attempt it?

Take some pics if you do!!
Not sure, but I would expect the wiring to be different on the B6 A4 compared to the 8P A3.
It's not something to be enabled on the B6 like it is on the A3 8P. I have retrofitted it along with an auto-dimming interior mirror, wing mirrors and auto headlights. Quite complicated, but not hard. The auto-dimming mirror is needed to tell the coming home lights when to turn on.

From that write up, I would imagine the coming home lights would come on whether it was light or dark - fine if that's what you're looking for, but will look to others like it's not working properly. Also, to follow that A3 thread, you would need to find out exactly what wires you are removing/replacing so as to do the same on the B6.
From memory, that looks like the wiring I used in mine, an F module is £230+VAT from a dealer and once you enable it, you will have a permanent yellow warning light in your dash (where the miles to empty/mpg is) that looks similar to the symbol on the new switch shown in the pdf guide.
It was done on a B6 cab sometime back, problem is the lights are on during the day aswell, as no sensor to distinguish between the different light conditions, so expect some quirks for sure, not really a substitute for the complete system, installed a fair few proper systems & its great with auto lights etc.