You say you just want to change the staked in front site? Just support the slide closely on both sides of the front sight, upside down. Using a narrow square faced punch, tap the front sight where the tail is staked, inside the top of the slide. Most are just staked, but be cautious as I have seen them soldered as well as staked. If they are soldered heat must be used to soften the solder before driving the tail from the slot. To replace there are jigs but it can be done without them. The front sight is fitted to the slot(there are large and small sight tails). The gas filled sights are very delicate and installing them a chore. Solder is of course out. Blocks are fitted on each side of the front sight blade so that they rest on the 'tops' of the side of the ramp of the front sight. The sight of course has to have already been fitted to a gapless state.. The site is held with the tail up, I use a vise but take care to NOT crush the vial... The slide is held upside down over the sight's upright tail. A staking punch is then used to peen the tail into is recess in the top of the slide. Excess is carefully filed/ground away and I usually wick a bit of Cyanocrylic glue under the base.. Hope I haven't left something out..CRS is really getting bad..