After a lot of investigation and some previous bad experiences with aftermarket head units I took a punt on Yatour bluetooth setup. I like the retro look of the 2004 being an old fart but wanted some connectivity and I fitted it today it was dead easy plus you also need an additional Y cable. Its controlled through the CD unit and streams music and the steering control works for the mode and track selection plus it automatically paired my Oppo Android phone. The best part is I didn't lose my s*** trying to get it all working and for only $164 AUD