Installing Radar 97 Cutlass Supreme

I have a 97 olds sutlass supreme sedan. I just bought a valentine one radar detector. I want to hard wire it so it turns on with the key. Any sugestions on where to hardwire it to. I thought about the map lights in the rear view mirror but i think if i did that i would have to have the lights on for the detector to work. Any sugestions would be great!!!!!
Thanks!!!

Iam not sure if this will work but u could wire it up like some who wires an amp to sub by connecting it to the back of the radio just attach it to the ing wire (yellow with stock radio i believe) and ground the other that should do it. it will come one like to radio does when the car is turned on.