Friday night and all of Saturday my friends and I installed my D3 in my '04 Audi A4. We also installed the XM Nav Traffic unit and the Bluetooth unit. We were able to use the factory GPS antenna (I had to do some splicing), but I couldn't get the factory XM antenna to work-It kept saying "check antenna". I also have Bose and was able to keep the factory amp and speakers. I did not hook up the reverse wire nor the illumination wire yet (where are these, I could not find them). It also turns out there was no accessory wire behind the radio, but my SWI-X took care of that. I will post some pictures soon. I also plan to do a small tutorial. Just thought i'd share.