When I used it on the anchor I shackled it between the rope rode and the chain, with about 12 feet of chain shackled and wired to the anchor. The snap hook could be shackled and wired to either side (to rope side or chain side) doesn't matter.
With Double Horizon I moved up to an electric windlass and bow roller -- so now I use the conventional setup of rope-chain splice, but I still carry a snap hook setup with a secondary (stowed) Fortress and rope rode for backup/stern anchor use.