Approached from the west having completed Seefin. Walked from there almost due east to the forest and up an old track. About half way up the trail ended at a new forest road that ran across the route, couldn't pick up the trail on the other side. So battled onwards and upwards, through densely packed trees covered in moss, peering for higher and higher patches of ground, till I coudn't find any more.

And eureka!

By a pure fluke spotted an old moss covered cairn with a rotting post sticking out in a tiny clearing that would be almost invisible from a few metres away. From the considerable rock around it, it might have been a large enough cairn before the forest enclosed it, roots pushed into it, and it fell apart. It clearly hadn't been touched by human hand for a long time. Continued east and pushed through a few more metres of thickly packed trees before emerging in the fire break/trail which I think is that identified by Jackill. From there it was south to the edge of the forest and west back to the approach road by Seefin.

Incidentally, for those who like such things, both Seefin and its sibling East Top have the same height, 491 metres. Even the Paps don't have that symmetry. Linkback: https://mountainviews.ie/summit/484/comment/14897/