Scosche FAI-3A into '04 Grand Prix GT

I'm in the midst of putting a 12" Rockford Stage 2 into a modified SubZero box into an '04 Pontiac Grand Prix GT.  The factory stereo is going to stay until a Pioneer indash DVD is purchased.  The question is, I have a Scosche FAI-3A putting into the vehicle and I can't get it to work.  Any help would be appreciated, especially wiring diagrams.  Thanks

I had problems with one of those, or so I thought, until I boosted the gains on the scosche unit and then it worked fine. Obviously, make sure your wiring is right. Other than that, make sure the unit is set to Line Out and you have the ground wire connected (I'm not sure if this is necessary but I did it anyways). Make sure the gains you boost are the Line Out gains at the top, not the other ones at the bottom (on the FAI-3A). I don't know about the wiring diagrams, I found mine here though for my car by searching. Maybe check with the dealer or get a chilton book or something.