Update:
Added a psd file with various diffuse map presets to change the color of the armor, as seen in the image section.
Choose a color layer, deactivate others, save using DXT5 compression as "graddragonaspect.dds" (you will need the nvidia dds plugin for photoshop, or GIMP), remember to include the alpha layer.
Then, place the "graddragonaspect.dds" you just created inside "SkyrimData exturesdlc02effectsgradients" folder, create and rename any missing folders yourself, following the structure above.
Enjoy