This is encouraging. Do you have any links to the other threads?
I tried searching, all I found was a bunch of people tapping into the rear speaker lines with LOCs for their sub woofers :)
Is anyone currently working on a line level pre-out modification for the factory Sync 2 and/or 3 audio system?
If not, does anyone have a schematic diagram or block diagram of the system so I can get started?
Many vehicles have pre-out solutions developed by enthusiasts like you and me...