Mercury Mariner 200, 225 Optimax Outboards Service Manual, 90-855348, Page 450Get this manual
4Place the thrust race on top of the thrust bearing with the wide flat side against the thrust bearing 7Assemble the forward gear installation tool to the forward gear, then place it down over the propeller shaftEnsure that the thrust race seats evenly onto the shimTap the thrust race down lightly with soft tool, do not damage the thrust race surface
50785Thrust RaceWide Flat Side
5Install load washer (12-37429) over 44-93003 propeller shaft so that it seats against the REAR shoulder of the clutch spline teeth55624 Forward Gear Installation Tool (91-815850) Forward Gear Spacer Shim Load Washer (12-37429) Thrust Race