AD inside floor structure?

[BlueJeep]

I'm wondering about the vertical panel in an AD cab that's between the under seat tool box and the gas tank area. I've already removed the seat riser, and I'm wondering about this piece. It makes sense to me that it may be structural, to help keep the back of the cab from sagging and to help support the rear body mounts.

This is speculation on my part, does anyone know for sure? I'm trying to decide where to mount my seatbelt retractors, and if this wasn't there it'd be much easier - but I don't want to cut it out to later wish I hadn't.