I had called Dynamat before about this and was told that there is no easy way of removing their product.
It may come off but with lots of residue left. It is worth a try.
I've had to remove Dynamat before. Like Levi said, there is no easy way of getting it off (at least that I've tried/heard about).

BE CAREFUL if you heat that stuff up, it is tar, when it gets warm enough to become soft it's really hot. You don't want this on your skin, you will be burned.
The best way I've been able to come up with is take your time with a razor blade; those new plastic razor blades really work wonders. The original Orange/Citrus based cleaners (not just orange scented stuff that you generally get now) really does help take off the residue.
I would suggest going and buying some dynamat and applying it to a scrap panel of metal before taking anything edged to your amp. I've removed it from two panels just recently. I forgot most of the technique, the first panel is all scratched up, the second panel didn't have a single scratch. Better practice than scratch an expensive piece of audio equipment.