That is not how you remove that trim. Check my Avin install DIY for directions.

It can be found here: http://www.xoutpost.com/bmw-sav-foru...-detailed.html

Edit: Wait, you are trying to install wires in the bottom portion for a reverse cam? Is it a license plate frame mounted camera? I believe the red reflector portions pry off. My DIY might still give you an idea of how it works, but I didn't run any wires in that bottom hatch. I did remove the trim though so maybe it will help.

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