How heavy we are to influence fuselage first (4,6)

I believe the answer is:

body weight

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'how heavy we are' is the definition.
I can't tell whether this definition defines the answer.

'influence fuselage first' is the wordplay.
'influence' becomes 'weight'.
'fuselage' becomes 'body' (I am not sure about this - if you are sure you should believe this answer much more).
'first' is a charade indicator (letters next to each other).
'weight' put after 'body' is 'BODY WEIGHT'.

'to' acts as a link.

Can you help me to learn more?

I've seen this clue in The Daily Express.

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