I resorted to doing this in UE 4.15.3 (due to that autocompletion bug in 4.16 and VS2017).
Just the position output:
// Called when the game starts
void UPositionReporter::BeginPlay()
{
Super::BeginPlay();
// ...
FString ObjectPos = GetOwner()->GetActorTransform().GetTranslation().ToString();
UE_LOG(LogTemp, Warning, TEXT("%s"), *ObjectPos);
}