[Sgtmonkeynads]

Just make sure it has the same name as the file you want to replace.
Then put the new file in the same loation as the file you want to replace.
should work everytime, just like the old one.
I don't think i have a single stock sound anymore after doing this, it can add a lot to the game with different sounds.

If your talking about speech files on the otherhand, it's done the same way but I don't mess with those, yet.