If you created a DIN sized deck, with CD

Can't see what you need the CD deck for, except on the odd occasion, that you are burning to hear your new purchase on the way from the store ( I keep a cheapo CD Walkman for that purpose and use the Empeg's Aux jack, but I don't remember using it in a year or so).

Surely, it would suffice to have a jack, so that you could input other formats: CD, Mini-disc or even cassette (if I'm on a long journey, I often buy a talking book at a service area and they're still mainly available only on cassette ( in the UK anyway)).

Apart from that, I think the concept is spot on, and not having the CD player will make a lot more room in the Din slot.