You can install everywhere but, the first time you install any FSDT product ( regardless if it's for FSX, P3D or MSFS ), it will ASK for the Addon Manager folder, which will hold all FSDT products together, so they can be updated all in one go with the FSDT Live Update
However, they must all stay together and, to prevent you from spreading them around, the installation folder is asked only the first time, then it's saved and all subsequent FSDT sceneries will automatically go there, so you won't risk having them in all separate folders, which will completely screw up the installation and the updates.
If you realized you don't like you original choice anymore, the one and only safe way to do this is:
- Uninstall all your FSDT product ( all of them, regardless for the simulator )
- Reply YES to the question "Do you want to remove the Addon Manager ?" made at the end. THIS is what allows you to choose a new folder on the next reinstall.
- Reinstall the first FSDT product ( it doesn't matter which one ), and notice you WILL be asked for a destination folder, which you can choose freely
- Reinstall all the others, and notice they'll all automatically go in the path you chose for the first one.
