Ducati MONSTER 821 Workshop Manual page 554

Note
Pay attention to the direction of installation of oil seal, spring must face outward.
Fit leg into the sleeve.
Install bushing (20) in its housing.
Fit shim (19).
With tool (E) part no. 88713.1096 push bushing/shim assembly fully home.
Insert oil seal (18) following the same procedure.
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