1987-1993 Mercury Mariner Outboards 70/75/80/90/100/115HP 3 and 4-cylinder Factory Service Manual, Page 367Get this manual
Drilling Outboard Mounting Holes IMPORTANT: Before drilling any mounting holes, carefully read "Determining Recommended Outboard Motor Mounting Height", precedingThere is 34 in(19mm) difference between outboard mounting holes in transom bracket
Lifting Engine WARNING
Make sure that lifting eye is threaded into flywheel minimum of turns and that hoist has minimum lift capacity of at least 500 lbs(227 kg) BEFORE lifting engine1Remove cowling from engine and plastic cap from center of flywheelThread lifting eye into flywheel hub minimum of turnsReplace plastic cap after installation2Connect hoist [minimum lift capacity of 500 lbs(227 kg)] to lifting eyeLift engine and place on boat transom
WARNING
DO NOT, under any circumstances, allow upper outboard mounting bolts to be closer than in(25.4mm) from top of boat transomUpper mounting bolts must never be installed thru shimsIMPORTANT: If using "Transom Drill Fixture" (91-98234A2), use drill guide holes marked "A" when drilling outboard mounting holes