@tar
The bit I used was about the size of the shaft/thread, or so I thought.. the smallest I owned.
I admit I DID go full speed.

I'm afraid I probably destroyed the board by now.

I was using a 1/16 drill bit made for all surfaces
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I took the bits to a local do it yourself hardware place (Locally owned ace) and they tried to sell me 2 things, a borer and this screw removal kit..

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I've tried all of them, none worked...

@matchaman The actual CPU / SOC is inside the black square you see. Not sure if the Pi Broadcom chip is enclosed in ceramic or plastic but it's just the housing that is scratched / slightly chipped.