I have a '02 Olds Intrigue and I'm trying to put in my aftermarket radio (Sony CDX-M630), my 1000 watt amp, and 2 Kenwood 12's from my last car. My problem right now is solely with the head unit. I got the Scosche GM035 wiring harness which said I would also need the Scosche FAI-3A Bose/Premium...