Gruff personnel fitted in perfectly, surly ultimately (7)
I believe the answer is:
throaty
'gruff' is the definition.
(thesaurus)
'personnel fitted in perfectly surly ultimately' is the wordplay.
'personnel' becomes 'HR' (Human Resources).
'fitted in' means one lot of letters goes inside another.
'perfectly' becomes 'to a t' ('to a T' or 'to a tee' can mean perfectly).
'ultimately' indicates one should take the final letters.
The last letter of 'surly' is 'y'.
'hr' going into 'toat' is 'throat'.
'throat'+'y'='THROATY'
(Other definitions for throaty that I've seen before include "Hoarse" , "roughly speaking" , "(Of voice) deep, husky" , "Like Hacker, maybe" .)