STI Undertray Removal

Lifting the car up and supporting it on jack stands, start to remove the under tray by removing the two 12mm bolts at the front and single 12mm bolt at the rear
Next remove the two clips at the rear by pulling down on the bottom part and gently rocking the clip towards the rear of the car. They can be a bit tight, but make sure you don't pull hard enough to break them as they can get brittle over time.
On each side remove the three trim clips by pulling outward on the middle component to loosen, and then gently pry the lower half out. After all of them are removed you can lower and remove the skid tray from your vehicle. Set it somewhere out of the way.