Here's a basic step-by-step install of a Head KM SCS barrel on a Coksai/Kokusai M16A2. I basically followed the instructions (scans at the end) and did the best with my meagre abilities to not mess it up. One thing that was required before starting was to drill a small hole into the barrel mount piece which you can see in the fourth photo to allow adjustment of the hopup without being required to tear it down completely. If I've made any mistakes please let me know and I'll update appropriately. I ask this as I still haven't had the chance to properly test this out yet. Thanks.

Dedicated to Sparky.