Overconfident people — Ernie, Ritchie and Fawkes? (4,4)

I believe the answer is:

wise guys

'overconfident people' is the definition.
(wise guy can mean an overconfident or smart man)

'ernie ritchie and fawkes?' is the wordplay.
'ernie' becomes 'Wise' (comedian Ernie Wise).
'ritchie and fawkes?' becomes 'guys' (Guy Ritchie and Guy Fawkes).
'wise'+'guys'='WISE-GUYS'

(Another definition for wise guys that I've seen is " Smart Alecs?".)

I've seen this clue in The Guardian.

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