Local wheeler-dealer or a trooper on the rampage (8)
I believe the answer is:
operator
'local wheeler-dealer' is the definition.
'operator' can be an answer for 'wheeler-dealer' (shrewd or manipulative person). I'm not certain of the 'local' bit.
'a trooper on the rampage' is the wordplay.
'on the rampage' is an anagram indicator.
'a'+'trooper'='atrooper'
'atrooper' is an anagram of 'OPERATOR'.
'or' is the link.
Can you help me to learn more?
(Other definitions for operator that I've seen before include "Person at switchboard, etc" , "Conductor" , "User of machine etc" , "Person who directs or controls, machine say (8)." , "Machinist -- or surgeon?" .)