This is the final trimsheet material created in Substance Designer and rendered with Marmoset Toolbag.
This is the visualization of the RGB mask in one of the meshes to display what areas the grunge will be applied.
Demonstration of The RGB Mask working with the trimsheet material. I created this by separating the trimsheet UVs and the RGB mask UVs in different UV sets and exposed them in the master material in Unreal Engine.