Posted some G&J Products ratchet screwdrivers on the G&J thread, but wanted to explain details about them. The design is copied from the Zachary Furbish patent 593157 (Nov. 2, 1897) assigned to North Brothers.
Disassembly requires removing the screw close to the handle on the sleeve and then sliding it over the selector while holding the selector down. Then the selector and two pawls can be removed. The handle is simply pressed on. To remove take a board and drill a hole sized to fit over the main body. Clamp body in vice with board close to handle and then use hammer on board to knock handle off.
Removing the shaft requires removing a keep (stop) on the backside of the main body closest to the screwdriver end. I found using a small jewelers saw and cutting a slot where the keep is allows removal. Picture #2 shows the backside and two keeps.
Re-assembly starts with first putting the shaft back in the body and replacing the keep. I used a washer with a flat inserted into the groove and then ground down to match the body.
Next put the pawls in. Note that if put in upside down, it will reverse the switch position for direction.
Put the slide switch in and slide the sleeve on while holding the switch down. Put a drop of oil into the screw hole and replace screw.
G&J post
https://www.garagejournal.com/forum/threads/gormully-jeffery-tools.425971/#post-11440847