Dillon's of Galway

I am currently looking for my great grandfather Michael Dillon born in Galway, Ireland. I know that Michael immigrated to the US and is found married in Chicago in 1870. He was born some time between 1839-1843. I am currently seaching a family from Glinsk, Kilbegnet and Dunamon. They are John Dillon and Margaret Kean who gave birth to a son Michael . He was baptised in the Catholic Church on Mar. 29, 1839. He had a brother Patrick. His sponsors at baptism were Peter and Maria Curley.

I then found a John and Margaret Dillon who immigrated to the US on May 28, 1860, on the ship Albert Gallatin. They have a son Michael and Patrick. They also have a Thomas, Maurice and Alexander. I do not know if this is the Michael who is my great grandfather but I feel I should search this family to see if it could be the family I am searching for. John's occupation on the passenger list is given as a shoemaker. 

I am currently searching US census information in 1860 and 1870 for this family, but so far have made no positive verification. 

If anyone knows of this family or has information that would help me I would be very grateful. Thanks!