Distance plays an important role when casting for Tenggiri. To achieve good distance, you need a proper casting rod. Something in the 7-8 feet range. This will allow you to cast further than your jigging rod which is probably in the 6 feet range. I use a thin diameter casting line with an approximate rating of about 20lb and a little more over a meter of 40-50lb Flourocarbon leader. This reduces resistance from both wind and water. A 6000 sized HG (High Gear) reel will help with the fast retrieval as it takes in more line per crank. ( Ideally, 100cm or more/crank) I connect my lure to a barrel swivel tied to the leader with a split ring. You can also use a solid ring instead of a swivel. I avoid snaps and barrel swivels with snaps. I do not use a wire leader as it affects the swim action.
Here is a summary of what you need. I will get to the tackle recommendation at the end of the post.
Rod: 7-8 feet Medium Action Rod (PE2-3)
Reel: 6000 Sized HG reel (Based on Shimano Size)
Line: 20lb Thin Diameter Line
Leader: 40-50lb Flourocarbon Leader
Lure: 40g Sinking Minnow
Barrel Swivel: #2
Split Ring: #4
Treble Hooks: #2
The application is pretty straight forward. Cast out your minnow. Reel in the slack line. This will prevent the lure from tangling with the line. Once the line is taut, open the bail arm and let out line. Control the line with your cranking hand. This will enable you to detect any bites as the lure is sinking. If you do get a hit, Close the bail arm and reel in the slack before you strike. Otherwise allow the lure to sink as deep as it can go. A word of caution, when fishing in areas with coral at the bottom stop at a meter or two above. The average sinking rate is about a meter per second in slow/dead current. The lure will sink slower in stronger currents so adapt accordingly. If in doubt check with the boatman on the depth and the structure at the bottom.
Refrain from adjusting the drag on the first run. They do not run for structure and have very soft flesh so you do not need a strong drag to start with. Instead focus on maintaining tension on the line as Tenggiri are notorious for swimming back towards the boat. (This is where the HG reel give you an advantage as you are able to reel in the slack line quickly.) Once the fish is below the boat, lower your rod and maintain the tension as you tire out the fish. Get the gaff ready as the fish surfaces. (do not try to lift the fish by the leader. If the leader line crosses the jaw it will get cut.) Once gaffed, knock the fish out before you take pictures. This will prevent any unnecessary accidents on the boat. (They thrash around for a bit if you don't knock them out) To retain the freshness of the fish, bleed it and get it into the cooler quickly.
Now for tackle recommendations.
Rods: Zerek Temptress, Major Craft Off Blow, Evergreen Ocean Hunter
Reels: (Daiwa) 4000 to 6000 (Shimano) Sized HG reels with a minimum of 100cm/crank ratio
Lures: Zerek Cavalla, Jackson PinTail (Lure Haven has an in depth write up on this product here.)
I am currently using the Zerek Temptress paired with a Shimano Twinpower SW 6000HG loaded with 20lb Mustad Wish Braid. Leader is 50lb Surecatch Flouromax. For terminal tackle, I use Shout solid and split rings and Sasame barrel swivels. For trebles i use owner ST66. If you have any questions, leave a comment and i will answer the best i can. Cheers!