Go ahead and get metal (4)
I believe the answer is:
lead
I believe this clue is a triple definition!
'go ahead' is the first definition.
(I've seen this in another clue)
'and' acts as a link.
'get' is the second definition.
(leading is a kind of getting)
'metal' is the third definition.
(I know that lead is a type of metal)
(Other definitions for lead that I've seen before include "Call the shots" , "Guide; precede" , "Be in charge of; metal" , "Guide, conduct" , "Take a position in front" .)