Full grid (apart from clashes and bottom line) apart from:
8d Any formerly rejected book rattles cages .....defn gives ARY..wordplay ...? R from Rattles inside a reversed book?
How do you get the bottom line?
How do you resolve the clashes?
It's the definition part that's entered in the grid (so there are n clashes in cells) the definition for 'z' should lead you to a list of uniquely numbered things in Chambers.
The clash for ARY is reversed in the clue.