Help needed: firewall plates wanted

[banpei]

I think the correct term is "punching" for this.
I have seen two types of punching so far.
Punched in Engraved:

Or punched out/punched through:

I think the difference is whether the cars came from the Tahara plant (A52/A54) or the Kanto plant (M21 or framenumber starting with a 5, e.g. AE86-50xxxxx)

BTW: I'm sharing these two examples as they are already publicly available on the interwebs.