1986+ Mercury 6/8/9.9/10/15HP 2-stroke Factory Service Manual, Page 52Get this manual
OUTBOARD INSTALLATION
SPECIAL INSTRUCTIONS On installations where control cables will frequently be removed and reinstalled after the initial installation (i.einflatable boats), barrel retaining plug has been supplied as an aid for installationUsing this plug allows the control cables to installed as set without further cable adjustmentInstall barrel retaining plug as follows: 1Without allowing barrels of control cables to rotate, remove cables with cable grommet from outboard2Install barrel retainer plug between control cable barrels3Wrap cable grommet around control cables