the pivoting trigger makes tha 1911 style screw problemic, and it's much easier to just square off ( a little angle, actually) the back of the trigger bar. its on the outside of the frame, so removal of the grip panel exposes it. pry it out and down out of the way. drill a hole into the side of the frame Install a roll pin, press fit and red loctited for insurance. file off the back of the trigger bar until the half cock notch does not "rub over" the sear, when the trigger's held fully back. You'll be amazed at how much it helps your shooting, especially mid range really fast shooting.