Mr. Argumentor
I fab shitboxes and shitbox accessories.
Two other possible solutions:true, other end of that is probably meaty enough to drill as a test
Use a snap punch and just hammer it a shitload. They usually heat strengthen them in such a way that they are incredibly brittle. I've been lucky enough to have them just break up eventually. Easiest method to actually break them up, you just sit there with a podcast on and snap the snap punch over and over.
If its possible for you to use a torch, you can heat it up till it color shifts, then if you let it cool naturally it will lose its temper and you can just drill it out.