The getaway car used in February's brazen daylight execution of ex-bikie boss Mahmoud "Mick" Hawi was stolen nine months before he was gunned down, with police releasing footage of the carjacking.
The notorious former leader of the Comancheros died in St George Hospital after he was shot multiple times outside Rockdale's Fitness First around midday on February 15.
The assailant fled in a grey Mercedes station wagon that was found burning in a nearby street shortly after the shooting.
Police are hunting a man who appears in CCTV footage of the carjacking in May 2017 when the owner was approached after parking in Fairfield East street and threatened with a knife.
The assailant, wearing a black hoodie, is described as a male in his early 20s and of Middle Eastern/Mediterranean appearance, about 175cm tall with stubble on his face.
Police are asking for the public's help in tracking down where the Mercedes was stored for the nine months prior to the Rockdale shooting.
"We know high-performance vehicles are often stolen for immediate use by criminal groups, but they can also be stored for sale at a later date," Detective Chief Inspector Steve Patton said in a statement on Thursday.
"It is likely the vehicle would have changed hands - possibly multiple times - so we'd like to hear from anyone who may have seen the vehicle during that time, whether in a carpark, secure building, or even at a storage facility."