Gotta luv that Exhaust story ... I've also got an exhaust story circa 1989 that involves Walker in SA - but it not A9L related so it can wait for another day ...
But I have another question that needs clarity and I must state hear and now that I didn't buy a VK in 85 ... I bought mine in 93 so I missed that buying experience .... however there was (apparently) at the time an issue with the noise emissions or something that fundamentally had HDT build the VK GPA with the OE exhaust (complete with chrome tip) and then fit the "Big Bore" (as it was called at the time) exhaust later either at the dealer or Bertie street ... but the Headers were definitely fitted as part of the A9L VK package at Bertie street !!!! ....