3rd row delete

I permanently deleted third row seats from my 97 lx450. Seats are in great condition with no tears or rips. Tan leather is soft to the touch, not cracking or brittle. Likely seen zero use in their 20+ years. Truck is stored indoors with no winters. Includes seat belt mechanism and...

What do you guys think. Approach A or B? I'm using a .5"x3"x40" aluminum bar across the factory seat anchors to support the plywood and tie other stuff into (future drawers, etc.). With 'A' It would be easy to recess the bolts into the plywood but then I'd have to deal with the recesses filling...