A couple of people have asked for this, I made one a while back. Use it, don't...whatever.
Just place the .iwd file inside of your 'main' folder and you're all set, this is for 4D1.
If you use Steam, I don't know if placing the .iwd file will work...I'm not experienced in textures using the Steam version. If not, just navigate to the 'main' directory of your game, open iw_06.iwd, and overwrite the original weapon_camo_hex.iwi file.
THIS CAMO REPLACES THE STOCK HEX CAMO FOR ANY PRIMARY WEAPON. To use carbon fiber, choose the hex camo.