I literally have over 200 mods and heard that fo London will prefer a clean install. Since I don't want to lose all my other mods or mess with them in any way, is it possible to install fo4 twice on my pc so I can have one copy just for fo london and keep my other heavily modded version intact?

I have a similar problem - Is it possible to download and use the GOG version of FO4-GOTY modded for FO-London, on a PC that already has the Steam version of the game already installed and still being played. I'd like to be able to still use the Steam version for standard FO4 (with the next gen update) and use the GOG version to play London.

A friend has installed GOG after Steam and they seem to try to share the same 'SAVE' area for save files etc, causing some problems. I'd like to do the same but I don't want any cross-overs, or have to cut and paste the relevant Save files each time I change game.

So is there a relatively easy way to install and use both games without interference to each other? If so what is it please.

Thanks

I've been thinking of just change the name of my install directory, and the documents directory to:

Documents\My Games\Fallout4_Orig
D:\Games\Fallout 4 GOTY_Orig

Then install in the same location again. and just swtich the directory names back and forth depending on which version I want to play.

Then if I want to play the original, I rename the directories like this, I remove the _Orig change in the directory above.

Documents\My Games\Fallout4_London
D:\Games\Fallout 4 GOTY_London

The installs really should conflict because only one is active at a time, and you just need two directy name changes...