@MosheKatz, could you post a reference? I'm in this situation and looking for answers. Thanks!

I think I found it. PRICE PFISTER 467213 MARQUIS DIVERTER HANDLE WITH 12 SPLINE BROACH. The cross-shaped part actually pulls off to reveal the stem and 12 spline broach. Thanks @jay613

@TetraDev , Did you ever figure this out? I'm curious, too. I think there are some installation instructions that mention 100lbs tension on anchors, and then suggest additional expected based on sqft of shade. Assuming you figure out expected load on the anchors, this sort of boils down to asking how much torque (sideways pull at what height) such dividing walls can safely take. For mine, I thought I might just do it and then remove it if I see localized damage forming (and switch to a dedicated post). I'm interested in anyone's answer... Thanks!

What is "demo drywall on walls"? If you mean demolish or demolition, then how would getting rid of drywall help with sound insulation?