Trunk found in north-west or south-east (5)

I believe the answer is:
torso
'trunk' is the definition.
(both can mean a person's chest)
'north-west or south-east' is the wordplay.
'north' shows that the letters should be reversed in order (in a down clue, letters go up or 'northward').
'west' indicates taking the first letters (I've seen 'west of' mean this (most west - leftmost - letter)).
'east' becomes 'rot' (I can't justify this - if you can you should give a lot more credence to this answer).
The first letters of 'or south' is 'os'.
'os'+'rot'='osrot'
'osrot' in reverse letter order is 'TORSO'.
'found in' is the link.
Can you help me to learn more?
(Other definitions for torso that I've seen before include "Roots out in trunk of the body" , "Body without head, neck and limbs" , "Trunk; headless, limbless body" , "Roost on trunk?" , "Piece of bronze" .)
