Where is WeMod installed?

WeMod, like many other apps, is installed in the AppData folder. You can access the install directory by using the Windows Run prompt(windows key+r) then copy and paste the following and hit enter:  C:\Users\%username%\AppData\Local\WeMod

Can I change where WeMod is installed?

At this time you cannot change the default install directory. You can move the folder above to any location but new versions will be installed in the default directory.