Pardon the brim remnants. Not pictured: the many prior iterations. This started as a head on photo that I imported into fusion 360 and scaled after some measuring with calipers. It’s not perfect, but it’s rapidly approaching good enough. The square indent is to help with orientation - although the part obviously is not symmetrical, it’s much harder to judge the home.
The mold was likely 24mm. There could be some shrinkage or a the shot of plastic was a bit light for that set.
Or, it was actually 23.22mm and the dimensions were calculated from another reference point, like PCB or LCD size. If anything, .22mm was supposed to be .25mm clearance.
Translating CAD into plastic and back into CAD can be a very strange thing sometimes.
Edit: I reverse engneer a ton of things in CAD. Sometimes just some calipers work, but for curves, pictures + calipers + gauges are the way to go. Sometimes, if you get core dimensions correct, the correct curves can “emerge” from the design itself, but that is a somewhat rare dark art. Pro-tip: A reverse engineered part is almost never going to be perfect, but almost always has the potential to be better than the original.