I got the source from www.archaeology.ie so no the GR arnt that good really. I zoomed into the map and worked out roughly where they were. Like I said in the notes, a fella living beside them hasnt found them in the 5 years he lived there.
For what it is worth my own feeling is that they are they to be found though. Let me know if your heading over that way, Id be interested in having a look again. Have a look at Loch Greine as well, its a lovely lake that is nearby. Linked in with the Greine/ Sun thing.