Not sure on how to fix them in position, but basically you put razor blades behind and around inside where your Cd player goes, so when said douche bag attempts to rip your shit out in an adrenaline filled theivery, he cuts the fuck out of his hands, hopefully doing some serious damage. Stories of it working usually end up something like, walk up to the car seeing glass broken, look inside the car to find the CD player moved, but in place, and a lot of blood in the area around your car.

95 Eclipse GS: 10.5:1, Crower 2's and MSII
186 WHP - 150 WTQ
14.697 @ 93.85 MPH......Gone, but not forgotten
99 420A Avenger: Given to my sister
99 GS OZ: Sold
03 Evo 8: Family Car with balls