I have been working on replacing the rear sight blade on my Model 19. When I picked up the revolver, the rear sight blade had been broken off. I ordered a replacement blade kit from Brownells and started my research on the correct way to replace it. Turned the windage screw until it snapped and pulled the head out which had actually snapped flush with the bottom of the head. I tried everything I could to get the broken blade out without any luck.So after more research, I drilled out the nut and was able to drive the old blade out. I was very careful in this step placing the firearm into a plastic bag to catch the plunger and spring. Finally got the old blade out but never saw the spring and plunger. Going back to the research, I discovered that the spring and plunger were actually in the head of the screw and not under the screw which is what I had been thinking. Went back to the head of the screw and found that the spring and plunger were still stuck in the screw head and the plunger still compresses. Any suggestions for getting them out or should I just order out replacements from S&W? It has been fun so far, Thanks