You were right Brian. It's definitely a Highland Copperhead (Austrelaps ramsayi).
It looks like it was in pre-slough (milky pupils and reduced lateral colouration for this species), making it more vulnerable to predation.
Another distinctive feature of this species worth mentioning is the dark edges of the ventrals forms a dark ventro-lateral stripe, which can be seen in the first pic.
Sax nailed it with the distinctive white 'sails' on the supralabials being the most characteristic feature of this species.