Firewall V2.0 LOL The anticipated 4 inch recess I did was not enough...unless I wanted the waterpump to double as a bumper. This is form fitting to the motor with clearances for servicing the engine while in the car. Albeit very stealth fighterish I am pretty happy with the results. Its all steel with a layer of fiberglas mat on the inside and ultimately the outside as well to sandwich the steel for a bit of sound deadening as well as sealing the inside from water. As you can see from the pics, I built a frame to actually bee the structure and then just sheeted it. the frame is the actual rigidity of the firewall, the sheeting is just there to seal up the bay, hence the sheeting being spot welded in.
Oh and excuse the mess of papers in the floor. I learned a long time ago that the easiest way to make templates for sheet metal work is to use metal flashing/duct tape because it sticks where you put it, it will only bend the way sheet metal will bend, and it sticks to your sheet metal to make it easy to trace your templates. Only downside is the huge mess of backing paper, lol