Proving to be fabricating it (7,3)

'proving' is the definition.
('turn out' can be a synonym of 'prove')

'be fabricating it' is the wordplay.
I cannot quite understand how this works, but
'be' could be 'go' (going is a kind of being) and 'go' is found within the answer.
'it' could be 't' (abbreviation. e.g. in 'tis) and 't' is found in the answer.
This may be the basis of the clue (or it may be nonsense).

'to' is the link.

Can you help me to learn more?