The consensus is that its very hard to do without damamging the core. You also break the lockadown mechanism, and most standard cooling mounts when you do it, so youl have to make custom soltion for those while your at it.

A lot of people have tried, but I have so far not actually seen one who managed to pull it off without killing the CPU. (im not saying noone has, im just saying I haven't seen one, even here on XS). on the other hand, I have seen quiote a few C2D's that this was attempted on, and where the core was ripped in half, or torn right of the CPU-PCB.

All in all, don't attempt it unless 2-3 degrees are super critical for you, AND you can afford to lose a C2D and get a replacement.

-Stigma