Saturday was Chevy truck time.
There id 59 year old underseal, black paint of unknown origin, blobs of filler etc.
VIDEO SHOWS IT BETTER.
https://youtu.be/0EWhlH9PPYA?si=kpciH2z_pYFDqJTC
Mate PaulY had problems with his truck
Eventually he got it sorted out.
Happy days.
Sunday morning I got back onto my cab and cleaned the firewall once I had figured it out the most effective method.
.