It is very easy not to get the drill centred. I was going the other way and replacing pearl/MOP dot markers on a Korean Fender Tele with black dots! The MOP was stuck in really firmly around the edges and the MOP broke up. Couldn't free the remains with a scalpel, which meant that the Dremel came out. Inevitably I strayed a bit and some of the holes became a bit wonky. I needed to drill the holes out as the replacement dots were wider than the originals but same came out a bit off-centre. Looks OK if you don't look too hard or close. Now just waiting for spring in the UK to start properly so I can re-finish the neck properly.