I’d already seen the damage when i bought the car caused by a master cylinder leak back in 2005 when it was replaced.
The surrounding paint work had bubbled up and the exposed metal work starting to corrode so didn’t want to leave this repair too long.
Basically removed the pedal box (and repainted it) removed rust, treated area with Kurust. Then undercoat and top coat.
Re assembled pedal box and job done.
Unfortunately the brake fluid damage has extended to the internal area under the pedal box in the foot well.
That’s another job another day.