Place for testing gun turned up, it's said (6)
I believe the answer is:
'said' is the definition.
(verbal as opposed to written)
'place for testing gun turned up' is the wordplay.
'place for testing' becomes 'lab' (short for laboratory).
'gun' becomes 'rev' (I've seen this before).
'turned up' says the letters should be written in reverse.
'labrev' written backwards gives 'VERBAL'.
'it's' is the link.
(Other definitions for verbal that I've seen before include "Spoken, oral" , "Communicated in words" , "Sound (the hour); find (oil)" , "Word of mouth" , "in speech" .)