So Gary wrecked the old ship (6)
I believe the answer is:
argosy
'old ship' is the definition.
'argosy' can be an answer for 'ship' (I've seen this before). I'm unsure of the 'old' bit.
'so gary wrecked' is the wordplay.
'wrecked' is an anagram indicator.
'so'+'gary'='sogary'
'sogary' anagrammed gives 'ARGOSY'.
'the' acts as a link.
Can you help me to learn more?
(Other definitions for argosy that I've seen before include "One or more large merchant ships" , "Old merchant ship" , "Large merchant ship (poetic)" , "Great merchant ship" , "A great fleet as Spain once had" .)