Instruments found in dead body turned over by doctor (9)

I believe the answer is:
trombones
'instruments found in' is the definition.
'trombones' can be an answer for 'instruments' (I've seen this before). I am not sure about the 'found in' bit.
'dead body turned over by doctor' is the wordplay.
'dead body' becomes 'mort' (I can't explain this - if you can you should believe this answer much more).
'turned over' is a reversal indicator.
'by' says to put letters next to each other.
'doctor' becomes 'bones' (bones can informally mean a doctor).
'mort' back-to-front is 'trom'.
'trom'+'bones'='TROMBONES'
Can you help me to learn more?
(Other definitions for trombones that I've seen before include "Their slides have seven positions" , "Brass instruments" , "Seventy six were noted!" .)
