For Sunfish
http://www.aopa.com.au/documents/GAAntiTheft.pdf
Seeing you've got a lot of good ideas you should design and manufacture your $30 anti theft devices and sell them to the owners of our 252 makes of aircraft in Oz. Think of the money you'll make with the competition selling their products for over $100 usd+!
After all, leaving my locked aircraft, out in a paddock, unattended near Hopetoun, Vic might come under threat from terrorists linked to 9/11 and you and others might be in danger.
Colt