I have a 2000 382 and my cabin headliner has come down to the point where I can no longer keep it attached above. It seems that the foam and adhesive have disintegrated and I get black little flaky stuff all over the cabin.

Has anyone else experienced this and what suggestion can you provide for a fix??

Sounds like every gm car built in the 80's. If the foam backer is all flaky you really have no choice but to rip it out and re do it. I hate the foam backing on headliner and vinyl for that matter. Don't use that again.