ETS2/ATS Blender Tutorial: The Look and Variant System!
In this tutorial I go over how to use the Look and Variant system for ETS2/ATS
Looks: Different textures on the same object.
Variants: Different shapes on the same object.
You shouldn't have that texture issue at the end of the video, not sure why that was there. May be something to do with a modifier or lack there of.