Good to know, thanks for clearing this up. After hearing more about thermal adhesive, I'm now having second thoughts about it. I want to get this right the first time, rather than an ongoing project that I improve later.
Also good to know! The self tapping screws sound easy.
I need to decide whether to buy CPU heat sinks locally, or pay international shipping for the pre-drilled heat sinks (eg MechaTronix, which can be passive, nice bonus)
I bought the tools to drill/tap, it will cost minimum of $50 (cheap Chinese electric drill + other bits needed). Probably around the same I'll pay for shipping the MechaTronix.
The possibility I'll make mistakes on my first tap & drill make me lean towards the pre-drilled heat sinks. I'm afraid I'll do a half-assed job and not know any better, and this will lead to heat issues and headaches in the future.