Hi, in my case i used a heat-sink from CoolerMaster Blue Ice Cooler, i removed the fan (40mm), it has a glue tape mixed with a metal conductor so you can make it glued and conductive, it works perfectly. There are other heat-sinks that work the same way, it's a matter of some research on those heat-sinks =< 40mm to get a better temperature, the diference of temperature is big, i haven't measure it yet but it should be near 10º, it's not even warm. If you have one of this kind heat-sinks that fit in the "socket" without the glued tape (most kind) you can resolve it with a glue named PRITT, i've already test it and works fine it seems those materials used on GFX/NB of notebooks, its a kind of glue that doesn't dry (gum).
Good luck