Hello,

 

I installed an F90BT awhile ago using the larger Metra harness for my 2007 Mustang, so I did not need to tap into anything around the car.

 

I'm about to replaced it with a new AVIC as well as add the XM unit. Where is the best place to get a constant 12v source for the XM unit?

 

 

 

 

thank you

Here is a connector view of the factory radio harness. I always tie my add on radio stuff like sirius, xm and what ever else not into the harness between the radio and the metra adapter. That way when I remove it from the car and into the next it all stays together. The wires for Ford are standard on all the 24pin radios. Some have other features and use more pins than others but all the pins are standard.