Chest Tattoo:
\Grand Theft Auto V\mods\update\x64\dlcpacks
\mpheist4\dlc2.rpf\x64\models\cdimages\mpheist4_ped_mp_overlay_txds.rpf

Sleeve+Back Tattoos:
\Grand Theft Auto V\mods\update\x64\dlcpacks
\mpimportexport\dlc.rpf\x64\models\cdimages\mpimportexport_ped_mp_overlay_txds.rpf

Face Tattoos:
\Grand Theft Auto V\mods\update\x64\dlcpacks
\mpsecurity\dlc1.rpf\x64\models\cdimages\mpsecurity_ped_mp_overlay_txds.rpf

Grand Theft Auto V\mods\update\x64\dlcpacks\
patchday4ng\dlc.rpf\x64\models\ped_mp_overlay_txds.rpf