If you slow troll Macks, go to heavier line. If they hit you bait, 40lb plus will not matter. The whole thing with light line is so the fish keeps moving in a free motion. When you are slow trolling, your bait is moving, go heavy line.
I have a great idea? Buy your own boat, cook your own grub and get skunked like most of the private boaters on this site that chase Bluefin! But the day that the sun and moon come together, their is nothing like being there!