Unreservedly confess to everyone (4,3)

I believe the answer is:

tell all

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'unreservedly confess' is the definition.
'tell all' can be an answer for 'confess' (thesaurus). I'm not certain of the 'unreservedly' bit.

'to everyone' is the wordplay.
'to' becomes 'tell' (I can't justify this - if you can you should give a lot more credence to this answer).
'everyone' becomes 'all' (I've seen this before).
'tell'+'all'='TELL ALL'

Can you help me to learn more?

I've seen this clue in The Globe and Mail.

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