So in the world of SINS modding you come to find 1 big pain in the **** that would be ICONS. Since Ironclad decided to make modders lives hell they made the file(s) containing the different hud icons and jazz all on one big .tga file, now with some photoshop'n skill you can take 3 years off your life and edit all these for your mod...
-or-
Create a smart mod tool that knows where your pictures are in realtive to what you tell it and it will auto swap the files for you! eh? Ship creator and stuff would be kick ass!