Uninstall WOP from your FS2004 file.
Rename your FS2004 file to something like OriginalFS2004, including the FS9.exe, FS9original.exe for example.
Rename GW3 installation to FS2004, rename the GW3.exe to fs9.exe and the WOP installer should dump into your renamed GE3 files.
The you get to return everything to their previous incarnations.
PIA.
The other option is to copy all the WOP files, including gauges, effects and textures from the FS2004 installation across to your GW3 installation.
WOP
only recognises a 'Valid FS9' installation, so if you are using one 'those' patches that we don't discuss it will refuse to go there as well.
The best solution is to set up your clean FS2004 installation first, let WOP install there and run the GW3 setup after the WOP routine has done it's thing.
I keep a complete 'original' clean FS2004 installation on a backup HD, it can be copied across and then tweaked if needed.
IIRC none of the Shockwave/A2A productions recognise any form of FS2004 that is Kosher.
