Rust on 914 rear trunk lid

[artluvr]

My 1974 914 has the typical bubbling paint on the rear trunk lid. I have cut out a section on the left side and removed the foam so I can treat the rust and weld in a replacement piece. Should I consider putting in more foam for rigidity?

Also, even though the right side has no rust pin holes, is it advisable to cut out a section on that side and remove the foam as well. I am doing all this to prepare the car for painting--my first attempt. Of course, I am a novice welder also

[RandyLok]

I'd argue the foam is the reason for it. Foam traps moisture. Why else would it rust up there?

[mepstein]

Originally Posted by RandyLok

I'd argue the foam is the reason for it. Foam traps moisture. Why else would it rust up there?

Correct.