Removing and restoring spring when removing shell

I have successfully removed the Instax shell, and managed to release the spring from the inside of the camera after a bit of poking around, however I have absolutely no idea how to get it back on there when putting the camera back together. I know the guide mentions the Phillips 00 screwdriver (which I have) but this is possibly a little vague for something that is quite fiddly and challenging.

Any tips on this?