bimbettocavallo

Hello everyone, new Porsche guy here!
Just got myself a 2009 Targa 4S and I'm making small cosmetic changes. One of them is deviated seatbelts.
I found many posts about removing the front seat belts, but nothing regarding the rear ones. If I missed some, please let me know.

Anyhow, I need to remove the plastic covers (circled in red), but to do that it seems like I need to first remove the vertical carpet piece just below the rear glass (circled in green).
But I cannot find an obvious way to do that.
Has someone done this? What is the right sequence?

Thanks in advance!