Heartiest congratulations on your succesful overclock.
Anyways i would not suggest you going for extreme cooling measures.
First of all they need a lot of skill to get everything in place and on top of that it is too risky.
Chances of failure are high.
I would suggest you try out water cooling first & then try these things.
As Masked mentioned above,please specify the FSB & Multiplier settings.
COnsidering that you have a KM266 chipset,that overclock is really very good.