2010 ford fusion sync wiring

Metra has a sync retention module.. but I have a feeling this is nothing more than a dummy breakout box. Can anyone get me the wiring schematic on the SYNC system? My vehicle came with the Sony Premium stereo w/out navigation. Don't think it matters.. but worth posting.

Hey bowdown, This may be a late reply, I remember you from another forum (and your sweet install job on the Fusion). Anyways, I finally got the correct wiring book today (seller sent a 2009 Fusion book by mistake). From all that I have studied so far, the stock radio box, aka "Audio Control Module" as Ford names it, is the actual device that controls the SYNC module(aka "Accessory Protocol Interface Module"). The SYNC module is connected to two different networks, the medium speed CAN network, and the high speed CAN network. The stock radio display module connects the the CAN network, as does the front panel controls. Without the stock radio, the SYNC system does not function at all. The stering wheel buttons feed into the stock radio box, and/or the SYNC module (depending on if you have navigation or not) It also seems, that there is line level audio outputs that are feed from SYNC to the stock radio box, but I have not been able to test this yet, as I have completly taken apart the stock radio box, desoldered the connectors, tuners and other parts. The Metra box interfaces with the CAN networks, to properly control SYNC. The SYNC module itself does not have a REM or accessory turnon wire, so I assume that the stock radio box communicates to the SYNC module via the data network, and using data, turns on/off and controls the SYNC module. SO all in all, the Metra unit is a computer, so to speak, that interfaces with the cars CAN networks, so direct wiring is not possible, you need the interface. However, I am taking a different approach to interfacing SYNC to my aftermarket system. I do not care to spend $130 for the Metra harness, and, since the stock box already does the interfacing, what I am working on, is stripping down the box, to just the circuit board. I will relocate the Sat and AM/FM tuner modules to lay flat on the board, and I will recase it in a slim case (possibly an old amplifier case). By creating a module out of the stock radio box, and essentially retaining the stock radio system, all I will have to do is tap the audio from the sync. The only thing I am stumped on so far, is finding some kind of connection, either in the sync module, or the stock box, that I can connect to the mute line of my aftermarket unit, so that anytime I get a phone call, or sync talks, it mutes whatever I may be listening to. Just like the stock system did. (This also means running the sync audio to a mixer that can remotely change input sources). Anyways, its a long term work in progress, as I have a lot of family stuff going on... If you need the schematics for the audio systems (or any other part of the 2010 Fusion), send me a PM