McCloskey /Cassidy/ Lafferty

I am looking for Francis McCloskey b abt 1830 in Ireland.
He is *not* one of the Dungiven/Derry McCloskeys because his yDNA haplogroup is E1b1b while the Dungiven McCloskeys are usually R1b.
Irish DNA experts are advising me to search in the outer reaches of Ulster, specifically the edges of Donegal and/or Antrim. This yDNA signature is also found quite clearly in Scotland, so look in places with a strong Scottish settlement.

Francis is Catholic and emigrated to Philadelphia, PA around the time of the Famine.
He was a sailor and was in the merchant marine, leading me to look in locations near the sea.

He married Ellen Lafferty (in the US) or Laverty as I've seen it spelled in Ireland.
I believe Lavertys are found in eastern Tyrone or in Antrim. Ellen was born in 1840, emigrated to the US with her brother Edward, married Francis in 1863 and died in 1873.
I want to believe that Francis and Ellen came from the same part of Ireland, as they settled in the same part of Philadelphia, where they met and married.

Francis had a sister, Ann McCloskey.
She married Rodger (sometimes Roger) CASSIDYin the 1860s in Philadelphia.
Roger was also a sailor and in the merchant marine with Francis, so they may have known each other in Ireland. They certainly knew each other in Philadelphia, where Roger met Frank's sister and married her.

All of the people mentioned here were born in Ireland between 1830 and 1840 and emigrated to Philadelphia, PA as a result of the Famine.
The exact emigration details are unknown due to the abundance of McCloskeys, etc emigrating to the US at this time.

If you give me a location to search, I'll be over!

Thanks!

Colleen McCloskey