See in my last a6 avant I had a full size spare in that, satin black like the other 4 alloys, and I used it loads of times….. on that occasion when you have just the one wheel need a refurb, used the full size spare for those few days….. and you aren’t restricted to 50mph like on a space saver…. Makes all the difference when your commute is an 80 mile round trip, motorways and dual carriageways as well as country roads….
I’ll measure the wheel well once it’s back from the body shop next week…. See if it’s possible or not