1987-1993 Mercury Mariner Outboards 70/75/80/90/100/115HP 3 and 4-cylinder Factory Service Manual, Page 29Get this manual
Switch Box 1Refer to wiring diagrams in Section 2D when connecting wires
a Switch Box Bushings J-Clip Bolt [Torque to 40 lbin(4.5 Nm)] Screw (Secure coil ground wires under screw) Coil Ground Wires (BLACK)