The bullbar is designed to match your truck's paint color automatically.
[Release] Trux Highway for Scania NextGen S/R incl. Template | 1.31 Painted Trux Highway Bullbar For Scania S/R 1.4...
To use custom colors or fixed textures, you can edit the .dds files (specifically cadre.dds and grill.dds ) found in the mod's folder at vehicle/truck/upgrade/trux/textures . The bullbar is designed to match your truck's