Who ever installed the Alpine Head Unit that was in the car did a pretty good job them selves destroying the factory harness. The factory plug was still there, but the person stripped an inch of insulation off the wire, twisted, and taped.
I'm a diesel mechanic by trade. I see wiring problems every other day. I'm not foreign to wiring..lol. A co-worker has a buddy who works at a GM Dealer. He gave my coworker his username and password to GM's SPO Tech Website, where I got all the wiring info and pin-outs, and Installed (cut the factory plug out, stripped, crimped, soldered, and heat shrinked) all the wires accordingly. The wires that I did not use in the factory harness got capped (using a piece of heat shrink with a 1/4" hanging over the wire end, then heated) so they would not cause an unintentional ground (short).
Its done as right as it can be, without using the quick harness that I was hoping I could use.
There is no system in the car. The only other thing I see that the previous owner had done is installed Kaption speakers all the way around. I have checked, and repaired, all of their improper connections.
Jay