Not quite the GWX files but your saved careers
This stuff you can simply copy over to ...\My Documents\... on your new HDD.
You have to reinstall SH3 though because Windows (most likely) needs the registry key for SH3 which gets established then. One of those annoying Windows habits.
Maybe it's also possible by locating the SH3 key in your current Windows registry, export it and reinstall it under Windows of your new PC. But that's a very unsafe idea, better do a reinstall
