Make corrections to pieces penned by editor (5)
I believe the answer is:
emend
'make corrections' is the definition.
(I've seen this before)
'pieces penned by editor' is the wordplay.
'pieces' becomes 'men' ('man' can be a synonym of 'piece').
'penned by' indicates putting letters inside.
'editor' becomes 'ed'.
'men' going inside 'ed' is 'EMEND'.
'to' is the link.
(Other definitions for emend that I've seen before include "Edit; make alterations to a draft" , "Modify" , "would appear better" , "Make correction in written material" , "Correct and improve the text" .)