Stroke by a night-watchman, for one, going amiss with ambition (8)

I believe the answer is:

offdrive

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'stroke by a night-watchman for one going' is the definition.
I don't know anything about this answer so I cannot judge whether this works.

'amiss with ambition' is the wordplay.
'amiss' becomes 'off' (I've seen this in another clue).
'with' means one lot of letters go next to another.
'ambition' becomes 'drive' (I've seen this in another clue).
'off'+'drive'='OFFDRIVE'

Can you help me to learn more?

I've seen this clue in The Irish Times.

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