I'm trying to take a human head skin, and make the back part of their heads close to grey or iron like color. I got the .dds texture file open in gimp showing the stretch face, it's just I have no idea what to do after that on how to properly change the skin, if I make a change and apply them in game the heads will lose all textures, and show a spooky white and black stripped face. I can get it working with armor, just not with human head skins.

Would there be some tutorial somewhere buried around these forums that talks about head/skin texture changes?

I'd like to do this as I thought it would be a nice bandage for the f2p_roman_coolus_officer helmet, as in game the helmet clips with the backs of their heads, so if the back of the heads has a iron color look, it would kinda blend in with the helmet and hide the clipping.