I work at a machine shop and have access to many machines. I planned to make the existing hole a solid size...say 2mm for example, then make a plug that is 2.1mm outside diameter, with a hole in the center of about .5mm (maybe less). I can freeze the plug in liquid nitrogen and insert easily into the 2mm hole, then as the plug heats up, it will have a solid interference fit, and no fear of ejecting out.
Your thoughts on this?