Be successful (3,5)
(Other definitions for get ahead that I've seen before include "Steal a march" , "At a hedge (anag) -- make progress" , "Make progress as in career, or take the lead" , "advance" , "The adage (anag) - make progress" .)
'be successful' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for achieve that I've seen before include "Produce" , "Effect" , "Bring about, accomplish" , "Attain (goal)" , "Attain successfully" .)
'be successful' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for go far that I've seen before include "Make real progress, achieve much" , "flourish?" , "Last" , "Achieve considerable success" , "Achieve great things" .)