Mercury Mariner 200, 225 Optimax Outboards Service Manual, 90-855348, Page 463Get this manual
5Install the forward gear bearing adaptor using hook tool (which was fashioned when the adaptor was removed) as shownEnsure that the adaptor seats evenly against the thrust race Final Installation (Non-Ratcheting)
1Install appropriate spacer shim into the gear housing
50881Hook ToolForward Gear Installation Tool (91-815850)Forward Gear Bearing AdaptorThrust Race
2Apply Quicksilver Super Duty Gear Lubricant to thrust bearing and install thrust bearing and thrust race onto forward gear bearing adaptor