Andy, I have that second bust you showed, and you are correct, they are all wrong. Many collectors have replaced the switch with a correct version, but required some knowledge of the process so as to not ruin it. I left mine as is.
The correct switch is almost like the face of a kitchen timer.
Haha yes, I couldn't think of a good way to describe it, but you nailed it! Ok guys, here goes... update #1 on the bust...
... So I have the 3D model mostly ready of the bust portion, still working on the head. I have essentially "punched" holes in the bust to fit the bulb and wiring, the switch and it's wiring, and areas inside for them to communicate. I don't have this properly scaled yet but I'm HOPING I can hide a battery in the very bottom part of the base but it may be too thin, we'll see. Either way I'm super happy with this all so far.
BTW that last image is just to show the hole running down the length of the bust along with the holes up top where the bulb and switch will go.