Many thanks Simon!
I didnt have any luck on the XC90 forums. The adaptor that I have seen is only available in Poland -
http://www.volvoforums.org.uk/showthread.php?t=201494
So have now decided to find a local aluminium tube bender and get one made up.
Do you have a photo of your modification. Also how is the backup box attached at the base and is the bracket adjustable or is it advisable to buy the box and measure up?
Thanks in advance
Steve