Best suggestion on lid (3-3)

I believe the answer is:

tip-top

'best' is the definition.
(thesaurus)

'suggestion on lid' is the wordplay.
'suggestion' becomes 'tip' (tip is a kind of suggestion).
'on' means one lot of letters go next to another (in a down clue, letters appear on others).
'lid' becomes 'top' (eg a bottle top).
'tip'+'top'='TIP-TOP'

(Another definition for tip-top that I've seen is " First-class".)

I've seen this clue in The Mirror.

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