If you use pure acetone, make sure you get some paintermasks (and preferably some latex gloves or something) too because the fumes could kill precious braincells.. leave that job to beer
Acetone works great. Fold a cloth that you can trash afterwards (a good example is an old undershirt), soak the center, apply that soaked area to the superglue, and make circular motions until it starts melting off, than just rub it down. Check your progess often because even a spec of superglue can screw up the contact with a heatsink.
I too will jump on the disclaimer bandwagon. I can't be held responsible, but you could probably sue my cat if something happened, because this is how he told me to do it.