Windage (left or right) on auto pistols is usually done either by loosening a screw and moving the rear sight or tapping it left or right with a hammer and brass drift punch. Elevation on a fixed sight pistol is done by replacing either the front or rear sight or filing the front sight to raise the point of impact. If an elevation adjustable rear night sight is available that isn't gawd awful big I'd go with that. It will make zeroing the pistol a whole bunch easier. If there are springs and parts under the rear sight you just need to be careful as you slide the sight off. Make sure you see and capture the spring. No biggie unless you loose it. Then you order the over priced little sucker and wait.......