I've seen the razor blades epoxied onto the underside and back side of the stereo unit. One of my son's buddy's did that after having several units stolen out of his Jeep YJ. One occasion he came out to take the Jeep to work and found a rather large amount of blood on the seats, carpeting and steering wheel. He came ove rto show me and ask what he should use to get the bllod out. (Hydrogen peroxide is the answer, just in case you're wondering)

Bill Mattson, Certified Old Guy
Monty-less (right now)
Laura Mattson, Certifiable
Get in, sit down, BUCKLE UP, shut up and HANG ON!!!