I already have the dds plugin for it but when I open a texture it just looks like a rolled out human that's been run over by a steam roller.
That's pretty much what we have to work with.
You have to kind of work out where it would be normally.
bear in mind that unless you name those new altered textures differently to work for a specific race, it will apply them universally to all people, unless that's what you want.
Alternatively, there's this mod, may make it easier for you:
http://www.fallout3nexus.com/downloads/file.php?id=2787