My mother is a Hehir from Feighroe, Connolly, Kilmaley, Parish, in County Clare. I have been researching Hehir's in an attempt to locate my ansestors. Carncreagh, also spelled Corrin Creagh, is in the Townland of Furroor, also in Kilamaley, but closer to Miltown Malbay. I have information on the family of Martin Hehir, in Carncreagh, born in 1941. Could he be a brother to your Great Grandfather. His wife was Bridget Crowley, and their children in 1901 included Patrick 17, John 15, Michael 12 and Martin 5.
Baptism records at Kilmaley Church show a son Joseph baptised on June 28, 1891 and a Peter baptised June 17, 1894.
The 1855 Griffiths Evaluation for Carncreagh lists Lott Hehir as the only Hehir. Could he be Thomas and Michaels father?
If any of this means anything to you, I would love to talk more.