(Edit: please excuse the various typos, I was in a hurry)
Ahhhh.... now it becomes much clearer. OK, like LBD2 says, trolling a CD18 rapala or some such would be a really good option for you.
Trolling surface lures, like marlin lures/ skirted lures is very very easy, they just sit behind the boat and you can go from 5-10knots and they will work.
These are marlin lures, is this what you had in mind? They will work for kingies, but are a little overkill really.
This mix of lures is some more like what you'd use for kingies etc.
The smaller "skirted" lures are good, and can run at a slightly higher speed than the hard body lures.
The lures in the top right are "Poppers", which are really intended to be used as casting lures.
The lures in the bottom left as "bibless minnows" and also are very effective on kingies, and have the advantage of being pretty much idiot proof to troll, always tracking straight and true. The three lures in the bottom middle with the big plastic "bibs", bibbed lures, are very good as they tend to dive to a better depth, and have a more aggressive, vibrating action, and are very very good on kingifsh. Trouble with these is that they can get "out of tune" or spiral out of the water, causing tangles in your lines behind the boat, so tend to be somethnig more used by people a little more experienced in running such lures. Also they need to run at a slower speed than the bibbless and skirted lures.
however as you see they can be quite effective! ;-) That lure there is the same as the pink/white and the purple one in the bottom middle of the pic above, so that gives you an idea of scale for some of these lures.
Poppers also catch kingies, obviously, you will have seen a lot of pics here of that I am sure...
... although this was obviously used as a cast lure, not trolled.
If I were you, looking for a nice, easy to tow lure for kingies and or big kahawai..... hmmmm... I tihnk a tuna-bullet style lure, that looks like a small fish or squid skipping along behind your boat....
somethnig like this, rigged on say about 2.5m of 150lb nylon trace, and a 7/0 stainless game hook in the tail of the skirt, would be the easiest and probably the most prouctive lure you could use, with the benefit of being deadly on small tunas like skippies and albacores as well if you run across a school of these. Yellwfin too... they really will take anything.
A couple of good kingfish sized minnows would be a couple like these (below). The top is an Elliots Mackerel Mauler, don't know if you'll find them anymore though, butsuch bibless minnows as these are a great size and action for kingies at pretty much any speed. The bottom lure is a yo-zuri hydro-magnum (I think), anotehr really nice lure in that I have always found these to troll easily straight from the box, whereas otehr types often require some rather skilled tuning to get them to swim well.
what I do not like about such lures is that they come rigged with trable hooks... and trebles are dynamite on any fish... so if you are likely ot be releasing any, please, don't use trebles, they chew a fishes face to pieces, it is not a good look and their survival odds arepretty damn low ater being hooked on these types of lures.
These are a pile of different skirted lures, all Black Magic ones, those down the right hand side are what I'd suggest ofr kingi trolling and tunas. Those on the left are marlin lures.
Hope this is a little help,
cheers, Stu.