Mercury - Helm Harness Quad Engine Next Gen DTS Helm Harness 84-8M0157219. OverviewThis harness gives a quad-engine DTS setup one clean path from the helm into the system. With four engines in the mix, keeping the wiring simple makes a big difference-this harness keeps things from getting crowded or confusing behind the dash. It lets the helm send throttle, shift, and system data without fighting tight bends or mixed-up runs. It's a straightforward piece that helps a big setup feel more manageab