Removing stuck on case foam

Just removed a keyboard from an Anvil flight case after years, and the foam has deteriorated and is stuck to the keyboard. Most of the foam comes off fairly easily, but there is a very sticky glue-like residue left. I tried a little denatured alcohol, but it seems to remove the paint along with the residue.
How do you clean this stuff off?

thanks!

Randy

Try distilled white vinegar.