Fiberglass repair on heater box

Dartsun said
Looks like riveted but detached. I can’t believe how gross it was inside this thing and I was daily driving it off and on for 20 years lol.
View attachment 1715534841

Yep, rivets. And like the others said, repair and support the area. Are you using a restoration kit? If you have access to a bead blaster I would clean everything so thing work and move better. mine was disgusting also!!! Huge rat nest, tons of rat crap.