Scraped the foam away in spots and sand with 60 grit for better adhesion. 3 dabs of RTV should do it. I remember now I did a similar repair on my 83 4 or 5 years ago and it's still holding up.
At the time I thought the aluminum backing was part of the dash lol.

RTV can be cut with piano wire if needed- not so permanent as some other adhesives.

__________________
85 300D turbo pristine w 157k when purchased 167,870 July 2025
83 300 D turbo 297K runs great. SOLD!
83 240D 4 spd manual- parted out then junked