Moose Oil: that's rocking song (1,4,3)

I think it could be either:

Which length description are you looking for?:

1,4,3

o sole mio

'song' is the definition.
(I've seen this before)

'moose oil that's rocking' is the wordplay.
'that's rocking' indicates an anagram.
'moose'+'oil'='mooseoil'
'mooseoil' is an anagram of 'O SOLE MIO'.

(Other definitions for o sole mio that I've seen before include "Neapolitan song" , "Italian original of Presley's It's Now or Never" , "It's Now or Never used this Italian song" , "Italian song anglicised as It's Now or Never" , "Air" .)

I've seen this clue in The Sun.

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