Some people zip tie them to the steering column and some people zip tie them to the wiring under the dash. Steering column seems to be front of the car biased. zip tied to wiring seems to not always work the way you want and sometimes hard to program. I like to use some double sided tape and mount them to the dash plastic or metal under the dash. I have mine behing my dash bezel. You can try zip attaching it to the wiring under the dash and then test it to make sure it works the way you want. Shut the doors, arm the alarm, and lightly hit the door frames to see how far away it reads and how well it picks up.