FYI - For anyone using the IMMO BLOCK defeat, there's a way you can hook it up to the car and not have to worry about changing the 9v battery. The battery lasts 2 years, but it's the type of thing you can forget, plus if the car ever changes hands, the new owner might not know the device is even installed. Instructions on how to do this :
http://www.ezimmoblock.com/battery-eliminator