Thank you very much! Never really figured how to do it. May I ask you how you made the black/white texture?
I'm using Photoshop for it. The picture is to make your image black/white the next step: go to the Tab: Image and scroll to levels and slide the arrows the white color is the specular effect
Attachments
When you press on it, it makes the image Black/White
Personally, I l keep my numbered textures from Sketchup and make Material files from those after making the specular maps for it. In that example, I only made a grey metal NL2MAT file and did a diffuse override for Yellow and Black on Aventador. Otherwise I only did an override if I wanted to adjust the color within NL without changing it in Sketchup because I'm lazy.
...If I remember correctly I only overrode the pool's concrete and the brick/stone walls for everything except the station. Other than that, I left the diffuse alone on all the others.