I am with Codprawn on this (makes a change eh!) but you need to use a wheelclamp as well.
Myself and Brian Taylor needed to dislodge the SAS clamp on his boat. Al it took was one clapped out Disco and driver and about 20 seconds to break through it!
So go for a bulldog bigboy that will take at least a minute! ( but the insurance companies criteria will be met)
Here it comes again, I don't stand a chance
Soul possession, Got me in a trance
Pullin' me back to you - Deja Voodoo