Distance: 8.1 km (3.0 DOC hours) - Tramping track - Moderate terrain
Altitude: 52m to 587m. Gain: 778m. Loss: 245m . Gradient: 7 deg (Moderate)
Skills:

Tramping track (4/9)
Cut, marked tramping track: natural, rough ground surface

Primary, unmapped (2/5)
Route not on maps, but is principal access to hut or along range / catchment

Moderate (difficulty: 3/5)
Occasional moderate climbs

Moderate (difficulty: 3/5)
Low scrub in open or bush / river rocks

None (difficulty: 1/7)
No alpine skills required

None (difficulty: 1/6)
No unbridged river crossings

None (difficulty: 1/7)
No alpine skills required

After walking along the road for 20-25 minutes, a road somewhat hidden in the bush with a wooden fence heads up to the left. If you get to the slip, you've gone to far and it is worth heading back.
Follow the road upwards. as it climbs steadily. In general it's fairly gentle but there are a couple of steepish bits heading around corners.
Towards 527, there is a split to the right. Carry on straight to get to forestry and a clearing on near 527, then turn right. The road seems a little ambiguous, but becomes obvious again. Follow the road along, climbing over a movable fence across it at one stage (about 1.25 hours from start). 15 minutes later follow the road on the right that heads down
The road carries on for much further than shown on the map, splitting onto a track at 540m (2.25 hours) following the ridge up to Panatewaewae (3 hours). Take care to stay on the ridge - there is a reasonable ground trail but it is easy to lose it when trees have fallen across the track.
Only the last 40 minutes up is on sparsely marked track, the rest is on well formed roads, though there are no signs showing the way. There are plenty of DOC triangles at the bottom of the road, but they seem to have run out up near 527.

Note: Described in the reverse direction to your journey

From Panatewaewae, head down the ridge through the bush. There is a reasonable ground trail but it is easily lost from time to time due to tree falls. The track joins an old road after about 40 minutes. Carry on straight ahead and follow this over several bumps. It is possible to drop down the main spur off 437 - just take care to go past 437 to miss a short gorgy part of the stream below.
Take the left turn at the junction of the main ridge and the spur heading down to 440 and carry on along, through pine trees until reaching the clearing near 527. Turn right again and follow the obvious road down to the old North Mangahao road end.
Only the first 40 minutes down is on sparsely marked track, the rest is on well formed roads, though there are no signs showing the way.