[Klemm]

Sorry mrbingle, not really knowledgeable on the subject, but could it be that you didn't use photoshop and forgot the alpha channels? And it could also be that you have to have all the textures of the cockpit alongside your edited one in the mods folder.
And are you sure that you created the right folders in the mods folder? It sure looks so, but there could be an error somewhere.
Sorry for being not more specific, just some wild guesses. And maybe someone more well versed in the subject comes along and tells you what it is. :?