I've had no issue taking them out using a small screw driver-like-tool that I made. Also, acetone will dissolve the glue if prying will not work. The hardest thing is learning to be patient and having a light touch. Remember, you're only using small "dots" of glue to hold them in place while you grind, if you place those dots toward the outer edges, then you're not left with much at the end. I tend to glue only the corners to make is much simpler.
May not be an acceptable answer, But Ive had to file handles before due to heat issues. Its suprising how fast a 10" bastard file will shape a handle. Not nearly as fast as a grinder, but an option.