I too was told that my relatives were from Nenagh but they are actually outside of Nenagh(I'm told about 5 minutes away) in Dolla. The parish of Dolla had 6 Cleary families according to Griffith's Valuation in 1851. There were 8 Cleary families in Finnoe. Kilcomenty 2 families. Kilvellane had 1 family.St. Patricksrock had 1 family. Templetouhy had 3 families .This info came from IrishTimes.com. Make use of Familysearch(LDS) and Rootsireland.ie .Also Ellis Island records.
The 1900 US Census puts them in ward 6,married in30 Sept. 1884,She is 37 and he is 43. There are7 children from 14 to 1 year old. He is a fish curer.The 1910 census adds a "u" to their name ; McKeough. There is info in the Mass. Town and Vital Records (BMD) too. The more info gathered, the more likely you might be able to trace back. Good Luck !