The drivers side arm rest / grab handle on the front door of my Datsun
280ZX, was quite flappy feeling, due to the breakdown of the hard foam substance inside it...I removed the arm rest, then lifted up a small section of the vinyil trim ( so as to get access to underneath it ) the squirted in a small amount of "Space Invader " ( expanding foam )...
I had to keep an eye on it as it was drying though...so as to keep it in shape.... but it looks great now...and feels like a new arm rest...nice and tight !
Cheers,
Brian Canham