The goal of this was to remove the "wheel" which locks the trigger. After I bought this, I found unlocking this trigger took some practice and I didn't like the way it made using the lighter so difficult. Of course your situation may be different. We have no children on the premises so I didn't mind leaving this trigger interlocking device off.
My disassembly instructions are brief and in some ways redundant to the more detailed step-by-step Scripto Lighter breakdown posted by an earlier writer at: https://www.instructables.com/id/Scripto-Lighter-Teardown/
As this is my first DIY instructable I wanted to practice photographing a project that had small pieces and using a SmartPhone camera. The phone is a T-Mobile Huawei called MyTouch. The Smartphone's camera is helped by viewing the small objects through a handheld strong magnifying glass. No flash was used. All photographs were done with the morning sunlight pouring through a window.
First, remove the small Philip's screw with a Jeweler's screwdriver, which comes in sets from places like Radio Shack. There is only this one screw.