hi everyone, i bought A4 B7 '06, but there is aftermarket cd head unit. i would like to swap it with original one, to access it with handle on steering wheel, plus all Bluetooth(i found its in my car but not sure what it does, so hope with original head unit it would work) and etc. the question is what kind of unit it suppose to be is there only audi concert made especially for b7 or i can put any single din unit even form vw or skoda?.