Being that you have already dine The below....

C: > Users > [Your Profile] > My Documents > My Games > Fallout 4

In Fallout4.ini, repalce the line sResourceDataDirsFinal=STRINGS\ (under the [Archive] section), with:

sResourceDataDirsFinal=STRINGS\, TEXTURES\, MUSIC\, SOUND\, INTERFACE\, MESHES\, PROGRAMS\, MATERIALS\, LODSETTINGS\, VIS\, MISC\, SCRIPTS\, SHADERSFX\ 


Just copy the DATA folder into your fallout 4 root directory

The DECAL DDS SHOULD be in the COMBAT ARMOR folder

DATA/Textures/Armor/CombatArmor


Simple...

Enjoy and thank you for downloading