From Hunters Hut, either cross the north branch of the Wanganui above the forks, or use the cableway/cage 1km upriver. The route follows the TR (north) bank to the roadend. A brief marked track sidles above Annoyance Bluff, but the remainder of the route is riverbed / riverbank on gravel and stones. Mystie Creek is bridged, and all other sidecreeks are minor. Real flood conditions will cover the route along the riverbanks though and make the track impassable.
You hit the end of an old 4WD track at Canopy Bluff, but after 300m that veers north onto proivate land and the public track is roughly cut through bush along the river escarpment. You soon rejoin the road however, and follow it to the carpark at the power house / info kiosk at the 2WD roadend.
Note: Described in the reverse direction to your journey
From the carpark at the power house / info board, a 4WD track follows the river for a couple of kilometers before veering inland over private land. A short roughly cut bush section follows to rejoin the road for the last 300m to where it ends at Canopy Bluff.
From here the route follows the riverbed/bank on rounded river stones and gravel. A few flats provide a break from the rocks. Mystie Flat is bridged and all other sidecreeks are minor. Real flood conditions will cover the route along the riverbanks though and make the track impassable. A brief sidle track is marked over Annoyance Bluff - a brief 30m climb - so just an annoyance rather than a big effort.
The north branch was fordable just above the forks (below Hunters Hut) when I visited, but the cableway 1km upriver provides year round access. Hunters Hut sits back from the river on bush covered terraces and cannot be seen from the river. The creek 200m upriver is the nearest access up onto the terraces from the riverbed.