Gentex Homelinke Mirror Wiring Help

I am in the process of installing the Gentex Autodimming Homelink mirror and cant tell how to power it. I've searched and saw some threads but they werent clear, Jefferson's thread about installing an autodimming mirror helped but i need more clarification on where to hook up the wires

 

probe wires up in the headliner/maplights with a test light/mulitmeter.

There are power (constant and switched) and ground wires up there. Just poke around and then tap them.

 

Thats what i was thinking of doing but for me its too risky, im bad with wiring, im jus gonna have the dealership wire it

 

Exactly what Lookylook said..... Prob the wires with multimeter.

Find the wiring for the MAP lights for constant power for the homelink.

Find the wiring for the temp/compass (ignition power) for the auto dimming (if you have it).

For ground, you can use the sheet metal that supports the whole console, just make sure you get the paint off and a good contact with the metal (lug w/bolt). We used a ring lug on the end of the wire, drilled a hole and used bolt/nut.