Mercury Mariner 4 and 5HP 4-Stroke Outboards Service Shop Manual 1999, Page 62Get this manual
IGNITION SYSTEM
COl Unit
REMOVAL 1Disconnect CO unit lead bullet connectors (a)BLACKIYELLOW COl unit lead (b) at ignition coil and BLACK COl unit ground lead (c) from ignition coil mounting bolt2Slide COl unit (d) out of rubber brackets (e)