compass, temperature mirror

I bought a compass/temperature mirror for my 2005 Pontiac Montana.
Is there a specific place to hook up for the 12volt power source. In
addition to that how do I pass through the firewall to hook up the temperature sensor which will be mounted on the grill. Is there any existing wiring that may be present from the factory. Thanks!!!

Earlier models that didn't have the Driver Information Center (compass, thermometer, fuel data) had the connector taped to the roof above the head liner. Depending on how much power it needs, you may be able to tap into that to gain access to a switched supply and to the temperature sensor leads.

I beleive GregA here did the procedure so you may check some of his threads or his site for more information.

I'm not sure about the 2005, but the link below shows what was done to my 2001 Venture. Most of the wires were already installed, just not used when I started. There are a few pictures on that page.

Install Temperature Sensor (http://www.my-chevy-venture.com/install-outside-temperature-sensor.html)

Take Care,