Hi all. I am hoping someone can give me a quick answer. I am hoping to buy some 18"alloys this weekend on eBay. But they have this thing where you put your details in and then you find out if they fit your car. Trouble is, every time I find a set none are compatible with my "56" A4 3.0 Quattro cab. Is this likely to be the case? All seems fine until I put cabriolet into it. Many thanks in advance.