A good "before" shot
The parts. I had to replace the Metra GM-OS4 wire harness for the PAC C2R-GM11 since I didn't have OnStar. I also had to use the low level outputs (RCA jacks) on the stereo since I had the Monsoon system.
First, let's find the battery
Yep, there it is, buried behind the passenger fender under the hood. The entire inner fender needs to be removed to replace the battery.
Start opening the dash by first removing the chrome trim around the gauges
Next, pull the black insert out. Takes a little wiggling and force.
Pop the crome around the shifter, then release the ring from the boot.
The boot can be pushed back in to the hole for protection.
Gently pop the plastic cover inside the handle. There you will find two bolts that hold the handle in place.
Now the dash can be gently popped out. Some wires are hard to disconnect, so it may be easier to just tie the dash assembly out of the way with some of the connectors still attached.
The center console area can be pulled out by lifting the back side up first.
Underneth, the parking brake sensor and a good ground can be located.
To take off the waterfall behind the seats, the corner pieces must be removed first.
Now fingers can reach behind the central piece and gently pulled free.
I placed the plate for the GPS antenna on top of the storage box on the backside of the waterfall
With everything out of the way, waires can be tied off onto existing wire harnesses.
I decided to pull some more plastic out of the way to make life easier
Pulling the metal off the surrounds the shifter alled me to tie my wires more sucurely.
The hole is tight for all the wires. I had to force my hand through the small hole to pull the wires in as the stereo got pushed into the hole.
Best to make sure everything works BEFORE putting everything back.