simonb,
Depends where you are in Scotland ... just had a removable Westfalia tow bar fitted to my Mk1 by Buchan's in Cambuslang.
Was a bit nervous taking my pride and joy to the east end, but when I pulled into their yard, my Q5 was the cheapest car there!
They did a really neat job, including the coding ... there's now a rectangular opening under rear bumper about the same size as the hatch that would be there if you had the factory option ... unless you knew it was there, you wouldn't know it was there ...
While I was doing my research, pretty sure saw that there are already tow bar offerings for a Mk2 ... posted an enquiry via their web site and got a prompt quote and response to further queries ...
OK, it's not a Mk 2 but can post pic's if you want to see ...
bobf.