Hi,
To be honest, if it was me, I'd clean it up and re-apply new paste. TOO MUCH thermal transfer paste can actually REDUCE thermal conductivity (because it causes a gap between the metal surfaces).
You only need enough to form a very thin layer between the component and the heatsink, just to fill the imperfections in the two surfaces.
I would use a clean dry cloth to remove most of the paste. The residue can be removed with a cloth soaked in isopropanol.
You only need apply enough paste so that it just appears at the edges of the component when the heatsink is fastened properly.
BE SURE to take precautions when dealing with ESD sensitive parts.
BE SURE to let the isopropanol evaporate before applying new paste.