Fit up and nail up sections when friend comes around (10)

I believe the answer is:

manipulate

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'fit' is the definition.
The answer and definition can be both to do with ownership as well as being verbs in their base form.
Perhaps there's a link between them I don't understand?

I don't understand how the remainder of the clue works.

Can you help me to learn more?

(Other definitions for manipulate that I've seen before include "Handle, manoeuvre" , "Use" , "Influence someone deviously" , "Doctor" .)

I've seen this clue in the Sydney Morning Herald.

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