[LukeFF]

There are two different textures for the Type IX. Navigate to the /data/submarine/nss_Uboat9 folder, and look for the DDS files with the T01 and T02 line in them. The game only uses the first one, but you can always rename the second one so that it shows up in-game. The only drawback to this is the Tarnmatte anti-sonar coating won't show up when it's fitted.