Well, there are 3 turms for the IX, so there are 3 different TGA files for it & there are 3 different dats for it.
If you download this -
http://files.filefront.com/IX+Textur.../fileinfo.html
You will find all the textures for all the IX boats & Turms all packed into JSGME format.
Even if you don't use them, they will give you a good idea of which files are needed to fully skin an IX.
It will also give you a good idea on the naming conventions.
Please come back if you need further help.