Honda SH300 Owner's Manual page 111

8. Replace the cap properly on the spark
plug, taking care to insert the protrusion
(6) on the valve cover into the hole (7) on
the spark plug cap rubber ring.
9. Install the remaining parts in the reverse
order of removal.
(6) Valve cover protrusion
(7) Spark plug cap rubber ring hole
(6)
(7)
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