Fussy person putting label around top of lid (8)

I believe the answer is:

stickler

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'fussy person' is the definition.
(I know this)

'label around top of lid' is the wordplay.
'label' becomes 'sticker' (synonyms).
'around' indicates putting letters inside.
'top of lid' becomes 'l' (I am not sure about this - if you are sure you should believe this answer much more).
'sticker' enclosing 'l' is 'STICKLER'.

'putting' acts as a link.

Can you help me to learn more?

(Other definitions for stickler that I've seen before include "One's insistent" , "Person who insists as on protocol" , "pedant" , "One's less than flexible" , "One insisting on correctness" .)

I've seen this clue in The Daily Express.

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