Corrections said to be needed for manuscripts (8)
I believe the answer is:
writings
'for manuscripts' is the definition.
(a manuscript is a piece of writing)
'corrections said to be' is the wordplay.
'corrections' becomes 'rightings' (an act of righting is an act of correcting).
'said to be' indicates a 'sounds like' (homophone) clue.
'rightings' sounds like 'WRITINGS'.
'needed' is the link.
(Other definitions for writings that I've seen before include "Literary compositions" , "literary works" , "literature" .)