Wierd little triangle Thingies

[Ascaris]

I just finished welding in my new floorpan and firewall (Can we hear an Amen!)

Originally, there were triangular metal pieces in the forward corners of the engine compartment that ran from the outer frame to the back edge of the floorpan/firewall, right next to the bottom jack support posts/doughnuts.

Is this something that I need to replace? Is it necessary to stiffen the frame or can I just leave it out? (this is a daily driver, not a racer)

Ascaris