### Clue: Finished with a thousand — unfortunate it's too much (8)
### Answer: OVERKILL 
 ### Explanation: Definition: it's too much
 OVER(finished;done with) **plus**(with) K(abbrev. for "kilo", prefix specifying a thousand of, as in "kilograms") + ILL(unfortunate;unfavourable, as in "it's an ill wind that blows nobody good" – twisted somewhat to describe the French horn as "the ill wind that nobody blows good").