When I try this, the mod simply dissapears from the mod list in the game. I've tried it several times.
Had that issue as well.
Make sure you don't have multiple layers of folders from unzipping/rezipping. When you're finished changing the version number the pathing to the info should be:
C:\Users\username\AppData\Roaming\Factorio\mods\Squeak Through_1.8.1.zip\Squeak Through_1.8.1\info.json
If it isn't similar to that it won't show up in your mods.