Everything is here - it's just not all in the right place. The chamber has collapsed and only one portal stone comes close to standing. This has split down its length in a very impreesive way, making the stone look fragile - no wonder it collapsed.
The capstone is almost a round flat disk that now rests on top of the other stones. Behind the tomb is a large slab, which I believe is probably the remains of a second tomb.
The tomb points along a broad, shallow valley in which there appears to be a large conical mound, slightly offset from the centre, but apparently inline with the axis of the tomb.
It is now rather crowded out by a nearby concrete cattle-crush/sheep-pen thing, which is just 10m away, but if you face up the valley then just a bit of barbed wire fencing and a few sheep (which were staring at me in a very funny manner) are all that there is to remind you of man's modern presence up here.
This is an explanation of (and a bit of a disclaimer for) the coordinates I provide.
Where a GPS figure is given this is the master for all other coordinates. According to my Garmin these are quite accurate.
Where there is no GPS figure the 6 figure grid reference is master for the others. This may not be very accurate as it could have come from the OS maps and could have been read by eye. Consequently, all other cordinates are going to have inaccuracies.
The calculation of Longitude and Latitude uses an algorithm that is not 100% accurate. The long/lat figures are used as a basis for calculating the UTM & ITM coordinates. Consequently, UTM & ITM coordinates are slightly out.
UTM is a global coordinate system - Universal Transverse Mercator - that is at the core of the GPS system.
ITM is the new coordinate system - Irish Transverse Mercator - that is more accurate and more GPS friendly than the Irish Grid Reference system. This will be used on the next generation of Irish OS maps.