Cheats go round following drivers for top car parts (4,5)
I believe the answer is:
roof racks
'top car parts' is the definition.
(a roof rack is a part on top of a car)
'cheats go round following drivers' is the wordplay.
'cheats' becomes 'rooks' (rooking is a kind of cheating).
'go round' is an insertion indicator.
'following' becomes 'f.' (used when citing page numbers etc).
'drivers' becomes 'rac' (short for Royal Automobile Club).
'f'+'rac'='frac'
'rooks' placed around 'frac' is 'ROOF RACKS'.
'for' acts as a link.
(Other definitions for roof racks that I've seen before include "Carriers for holding luggage on tops of cars" , "car parts" , "Cars may have these fitted" .)