In water that deep you could use one of two rigs.
A running rig like you described, but dont use a three way swivel. Just the sinker on the bottom and them 2 m of 80 lb flurocarbon with a 8/0 circle running on the main line via another swivel.
The other rig is just a normal rig. J hook, 2 m of fluro trace, swivel and sinker on the main line.
If you are serious get 80lb braid on your reel, a braid capable rod.
Flurocarbon is the answer to kingys. They cant see it.
I do a lot of live baiting and its very successful.
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