That structure is critical. Have a look sideways on how the front legs on a PV work. The front chassis leg splits into a Y. The top half is welded onto the bulkhead. The bottom goes under the floor and ends at the crossmember the seats sit on. If you look underneath it is seam welded the back. The front chassis leg cantilevers against the crossmember, and it in turn feeds it load into the sil and transmission tunnel.

That is also why the transmission tunnel should be complete and structurally sound, especially on a powerful PV.

It is a U section with 2 reinforcements welded in where the seat supports go.