Logitech C-170 Faceplate

The FOV of the C-170 was far too narrow for a buildplate mounted camera stand, so I got myself a set of clip-on lenses for smartphones. With the 0.36x wide-angle lens the C-170 shows the whole bed. I quickly sketched up a replacement with a thread for the smartphone lens.
Since I could not determnie what thread exactly is on the lens I made an aproximation with an ANSI 17mm X 1. It does not screw in completely, but the fit is tight enough.
Should I stumble over the right dimensions for the thr