Motorworld used to sell a tool called a gator grip. It was sold as a universal size socket and was made up inside of loads of little pins that moulded to the size/shape of the nut. But it was very usefull to wheel theives as it would fit into any locking wheelnut pattern

Dont know if you could get hold of one of those??

http://www.fasteronline.co.uk/gator-...et-p-2990.html

Lee