It, for example, requires change of kit in port on the Mersey (4,5)

'it for example' is the definition.
(It is a novel by Stephen King)

'change of kit in port on the mersey' is the wordplay.
'change of' indicates anagramming the letters.
'in' indicates putting letters inside.
'port on the mersey' becomes 'bootle' (Bootle is a Merseyside port).
'kit' anagrammed gives 'kti'.
'kti' inserted into 'bootle' is 'BOOK TITLE'.

'requires' is the link.