Modifying a Texture
From Elite Wiki
Textures or skins are 2D graphics that are wrapped around 3D objects by the game.
Location of files
The textures are stored as .png files in the /Textures folder. Which /Textures folder depends on whether the object is part of the standard game or part of an add-on.
$PROGDIR/ Oolite.app/ Resources/ Textures/ <-- Textures for standard ships live here. Addons/ ShipX/ Textures/ <-- Textures for ShipX live here. ShipY/ Textures/ <-- Textures for ShipY live here.
Ship textures usually carry an obvious name e.g. ShipX_body.png. But not always. To confirm which textures are loaded for ShipX open the file shipdata.plist in a text editor.
$PROGDIR/AddOns/ShipX/shipdata.plist
<key>ShipX</key> <dict> ... < > ... </dict>