Installation:

Replace the files in:
update/x64/dlcpacks/patchday8ng/dlc.rpf/x64/models/cdimages/weapons.rpf
update/x64/dlcpacks/patchday3ng/dlc.rpf/x64/models/cdimages/weapons.rpf
update/x64/dlcpacks/patchday2ng/dlc.rpf/x64/models/cdimages/weapons.rpf

*Make sure to back up your files!*