First put tape or parts of an aluminum can around the pin as mentioned above to protect the scales if you slip. I have used about three layers of tape in the past. You can use a Dremel or file to slowly & carefully get rid of most of the head but make sure it stays cool. Just go slow. This way it will make the head weak. Then find your center & use a 1/16 drill bit to carefully drill it. The weak head should pop off & as long as you're on center, it will work out just fine. If you happen to get off center some, drill at an angle toward the center for a bit then drill straight down. You will see whan you have your center. I have done this many times successfully.