I have read somewhere that it is nice to have a disposable firewall that you can see through. I picked up some 3/32 acrylic in the aircraft section of Home Depot. Laid the real firewall on the acrylic, traced, drilled and finally cut with a saber saw. Now when I mount something to the firewall I can see where it is going to come thru and if I need to reposition something I can simply re drill the holes and not be concerned with Swiss-cheeseing the real stainless steel firewall.
Plexi firewall--also shown is nylaflow brake line and Matco parking brake valve.
