Ace blokes, fit and willing (8)
I believe the answer is:
amenable
'willing' is the definition.
(synonyms)
'ace blokes fit' is the wordplay.
'ace' becomes 'a'.
'blokes' becomes 'men' (I've seen this in other clues).
'fit' becomes 'able' (similar in meaning).
'a'+'men'+'able'='AMENABLE'
'and' acts as a link.
(Other definitions for amenable that I've seen before include "Agreeable and accommodating" , "Willing to be guided, being nameable" , "Helpful" , "Open and responsive to suggestion" , "likely to cooperate - with 3a" .)