Searching for Connor(s) ancestors in Kerry (West Iveraugh Peninsula)

Hello, 

I am traveling to Ireland in August of 2025 to look for the family of my great-grandfather, Thomas Jerden/Jefferson (T.J.) Connor. I don't have much to go on. T.J. was born in 1865 and came to America in 1870 (1900 US Census, the first census we can find him on), and he disappeared sometime around 1910 after marrying our great-grandmother and having five children. Family lore says his mother was Mary, and he had three siblings, Bennie, Jim, and Mary. We have no data on his father or the birth order of the children or if they were born in Ireland or the U.S. 

Other data: 1900 US Census shows he was naturalized but we don't know when or where. His sons, in birth order, were Willie, James Richard, Joseph, and Thomas J. His daughters, in birth order, were Alice Geneverie, Mary Belle, and Rachel Elizabeth. This census is the only U.S. record we can find for him. 

The census also shows his birthplace as Wales but he told all his children he was from Ireland. My DNA, and that of my only cousin on T.J.'s side of the family, tracks us to West Iveraugh Peninsula. 

I found a Catholic baptismal record dated Sept. 8, 1865, in Moyvane that shows a child, Thomas, was the son of Thomas Connor and Mary Keane. Godmother was Margarita Sexton (no godfather). We do not know if the family was Catholic or Protestant. Keane is a name that appears a few times in our DNA matches on Ancestry, but that doesn't confirm whether or not this is a good lead.

A ship manifest from 1869 shows a family, John and Mary Connor, immigrated with their son, Thomas, who was three years old. This ship (Etna) entered via Castle Garden/Ellis Island but we do not know T.J.'s port of entry so this may or may not be a lead. We have searched manifests from this time period fairly extensively.

Can anyone offer any guidance on how to search Irish church records and other sources most effectively when we get to Kerry, or any other advice on how to make the most of our time there?

Thank you for any assistance anyone can offer.

KCVH