Projects like ollee Watch seem to be able to stash it behind the front crystal or underneath the LCD.
Ollee does that by replacing the original PCB. In this project the movement is kept original.
I recall the blog n-o-d-e did successfully put an NFC chip inside while also retaining the default PCB, so there is at least some free space in the case...
https://n-o-d-e.net/casio.html (0:56)
alt Hacker News
Ollee does that by replacing the original PCB. In this project the movement is kept original.
I recall the blog n-o-d-e did successfully put an NFC chip inside while also retaining the default PCB, so there is at least some free space in the case...
https://n-o-d-e.net/casio.html (0:56)