Based on THIS
diagram and the similarity of your floor plan to mine, it might be where mine is.
Open the two storage bay doors in front of the duals on the passenger side. There should be a long access panel along the top that has a bunch of screws holding it. It could be behind that panel.
Note that the panel probably has a very aggressive black adhesive caulk. I had to use a flat pry bar to lift the panel enough to use a pair of shears to cut it and lift and cut and so on.
I took the gas struts off so I could raise the doors enough to get easy access to the screws along the top of the access panel.