Indicate concern as King tries a ramble after lunch (6,1,4)

I believe the answer is:

create a stir

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'indicate concern' is the definition.
I know nothing about this answer so I cannot tell whether this works.

'king tries a ramble after lunch' is the wordplay.
'king' becomes 'CR' (short for Carolus Rex, King Charles in Latin).
'ramble' indicates an anagram (I've seen 'rambles' mean this).
'after' means one lot of letters go next to another.
'lunch' becomes 'eat' (to lunch can mean to eat lunch).
'tries'+'a'='triesa'
'triesa' is an anagram of 'eastir'.
'eastir' put after 'eat' is 'eateastir'.
'cr'+'eateastir'='CREATE A STIR'

'as' is the link.

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I've seen this clue in The Guardian.

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