A simple trick which can help with shaving the TX's ears to fit, is to rivit/screw the helmet pieces together, then drill the ears where the screws will need to be, then line it up and drill the holes through the helmet. Then install the fastening screws for the ears with the long legs facing out (I've referred to it as the screws-out method). Doing so will allow you to line the ears up in exactly the same place each time. 

When you are shaving and sculpting the ears, what I found as the best method is to:

  • slide the ear on the screws to line the ear up
  • pinch the ears at the against the helmet (by putting pressure on the inside of the helmet in between the ears and