The cheek, bundling one onto the ship! (7)
I believe the answer is:
galleon
'ship' is the definition.
(type of ship)
'the cheek bundling one onto' is the wordplay.
I cannot really understand how this works, but
'cheek' could be 'gall' (both can mean outrageous behaviour) and 'gall' is located in the answer.
an anagram of 'one' is 'eon' which is present in the answer.
No letters remain.
This explanation may well be incorrect...
'the' is the link.
Can you help me to learn more?
(Other definitions for galleon that I've seen before include "Spanish treasure ship" , "All gone (anag.)" , "Large Spanish sailing ship of yore" , "One might sink" , "Historical warship with three or more masts" .)