Right, and Crutchfield sells Line-Level-To-Bose adapter connectors. So the gentleman who called Crutchfield and was told "we don't have any information on Audi Allroads" should try again and see if he gets anywhere by telling them "I need an adapter to connect an aftermarket stereo to a BOSE sound system". That will at least take care of the electronic portion of the installation.
That still doesn't help locate an adapter fascia for the dashboard, but I'll bet my eye teeth that the Allroad dash is the same as at least one of the other Audi models, and an adapter fascia will exist somewhere. All we need to do is find out which other Audi models have a fascia that is the same as the Allroad.
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Tony Fabris