As Frank said, solvents can be a double-edged sword. MEK (methyl ethyl
ketone) or ethyl acetate will come closer to dissolving the adhesive,
but also the underlying acrylic. Personally, I'm surprised that the
IPA didn't damage the underlying acrylic.
If you go the mechanical route, consider cooling the adhesive in order
to stiffen it. That way the energy you apply to it will go into
breaking it and not just deforming it and then letting it bounce back.
Ice is the handiest but messy, an ice block or an ice wrap is better,
dry ice would really be great.
Aspen Research, -
"Turning Questions into Answers"
Opinions expressed herein are my own and may not represent those of my