Guide and pictures credited to Jack Millin.
Flat bottom steering wheel off a S3 8P fitted to my 2010 B8 Avant. The electrical plug needed 2 little tabs trimming off and 3 of the wires de pinning and putting in different positions and it all works. I've attached a picture of the wiring guide as well.
This guide should also be applicable to the b7 A4 too.