Weak firewalls?

[deathsled]

I happened upon a discussion about the alleged weak firewall on early Mustangs.  Apparently the brake pedal application can cause the firewall to flex.  I also have a clutch pedal.  The car is not tracked but are there any potential nasty surprises I might encounter with anything breaking or bending with the current pedal setup? 

This is the starting point of a video showing a totally modified 67 fastback where the topic was mentioned.
https://youtu.be/RazJt1rESh4?si=s1qbdQBGKFnwac8I&t=907

I got to researching the issue (as I am want to do) and apparently Hane Performance (Walt Hane who raced and won the B Production in 1966 in an R Model) created a solution.  Not something I would really want to do to a street car and especially not to 6s843 but I don't like surprises while out on a jaunt.
http://haneperformance.com/Firewall-Brace.html
https://youtu.be/RazJt1rESh4?si=s1qbdQBGKFnwac8I&t=907

Apparently no new holes need to be drilled.  It looks awkward but perhaps necessary in a car with metal that is 57 years old? 

As an addendum, I can really recommend Hane's book "Racing to Riverside."  It was a very enjoyable read and he really analyzed the weaknesses he found in the R Model that he modified to make the car indestructible during the racing season in 1966.  The ingenuity he used on his R model was inspiring to say the least. I have no proverbial dog in the fight.  Just passing on a good read.
http://haneperformance.com/index.html

[CharlesTurner]

Could very well be a weak area, but under normal driving conditions, shouldn't be a problem.  I've never noticed the area bent or cracked on original cars and ones I've disassembled.  If I remember right, 67-68 do have a reinforcement area there, spot welded in.

[deathsled]

Since my car is seriously a day two car, I will consider Hane's option in light of the fact that there are no new holes needed to be drilled and it is a bolt on bolt off part.  Thank you for your analysis.