Hey... Here's what it looks like installed. Not working yet, however, as I'm waiting on the GMOS-LAN-04. If anyone has experience hooking up an aftermarket stereo with the LAN-04 please let me know! I need some help getting it going (have started a few threads in the Audio board).

 

looks sweet

 

Its exactly what Im hoping to get, how much did it cost you, if you dont mind me asking?
And I hope you get it running. However it will work fine now without the harness.

 

It will work fine without the harness? How's that? You can get the W505 for $800 now from Crutchfield. After the bluetooth and GPS you'll have about $1200.

 

As I said in the other thread (you have a few on this subject now) the lan04 is only needed to retain the onstar and door chimes. Other than that, its just a convenient way to connect the wires together.
Most stereo shops can clip the plugs off and wire up the head unit for about $50, or you can do it yourself using the diagrams I posted in the other thread and matching up the wires with the diagram for your head unit.

 

Oh wait, now that you mention you have the GPS option on that head unit, you would need the lan04 to give a speed signal for distance tracking. I think thats an aspect of the GM databus and not a direct feed, since the lan04 harness has a GPS wire, it must do the conversion.