1987-1993 Mercury Mariner Outboards 70/75/80/90/100/115HP 3 and 4-cylinder Factory Service Manual, Page 355Get this manual
Ride Guide Steering Attachment Extension Couplers Outboard Center Line Distance 22-12 inthru 24-12 in(57.2cm thru 62.2cm) 23-12 inthru 27-12 in(59.7cm thru 69.9cm) 26-12 inthru 30-12 in(67.3cm thru 75.5cm) 30 inthru 34 in(76.3cm thru 86.4cm) Required Coupler(s) Between Steering Eyes (Shown Below) 12 in(30.5cm) Coupler
15 in(38.1cm) Coupler (Supplied with this kit) 18 in(45.7cm) Coupler
aCouplers Connected TogetherLockwashersCoupler Link RodTorque to 20 lbsft(27.1 Nm) into End of Each Coupler
Couplers Connected Together with Coupler Link Rod