Adding Decals to some vehicles
Only vehicles with the RHS_GroupMaterialController component can use this guide. It seems that some other mod makers are also using the RHS component.
The numbers appear in order of GROUPX, so GROUP1 would be the first number, and GROUP3 the last. So the image would have the ID 121 painted on the back.
Some vehicles can also have a label added, some might only have the label as an option.
The labels are taken from the RHS_Content_01/Assets/Vehicles/SharedMaterials/decals/numbers/data/labels.emat file
As of writen this guide the current labels are these
For more on numbering read https://github.com/Global-Conflicts-ArmA/gc-reforger-missions/wiki/Vehicle-Numbering