This is exactly where I am at with my installation. I installed my factory Nav radio from my 2007 Grand Prix and it is unlocked and it sees the satellite with the $20 antenna I bought on Amazon. Now I need to connect the wire from the head unit to the VSS wire on the PCM harness. Does anyone have a picture of the PCM system for a 2004 to 2008 Grand Prix? It could really be useful. Where is this box located?
Thanks, Regards,
John L.