As the mod sswilson said .... 90%+ proof isopropoline from the pharmacy is a must to do so for this or whipe down anything you resell. :thumb:
Use tp / pt / ft to whipe off the initial amount to carefully not make it build up along the edge of the heatspreader till you see it & it just looks like its lightly smeared all over it but can read the lettering on it. Then take a fresh piece of whatever you used before ... douce most of the surface of it fairly moistly that your going to use to whipe it off on with the isopropoline & proceed to clean the outter edge of the heatspreader if paste has gotten on it. If there clean/clear proceed to do the top till its clear & looks how you got it out of the package or else repeat mentioned step of fresh material/isopropoline.
Make shure the surface is free of any dust/lint/tissue/towel particles when finished before re-applying your paste or repackaging it.