Mercury - Joystick Assembly for Multi-Engine JPO Control System 8M0178012. OverviewThis joystick assembly is the core control piece used in multi-engine Joystick Piloting setups from mid-2016 onward. It gives the helm a smooth, steady feel, letting you make small directional changes without overcorrecting. The movement feels natural-easy to nudge, but firm enough that you won't bump it by accident. It drops in as a direct service replacement for boats already running Mercury's JPO system.. Key F