Hi George; If your McCourts have records from Ellis Island, then I think that they must have arrived here during the 1800's? Atrim is and has been a origin for many McCords/McCourts.
There are two McCourts who have done Ydna testing with Family Tree DNA and within the McCord Group for comparison. It appears that McCourts and McCords are from similar very ancient origins, but did separate some time ago.
Some McCourts left from the Eastern seaboard and migrated to Canada as well. Some McCourts also changed their names to McCord. That could have been from mistranslation of dialects or, at times, people wanting to be less "Irish". Both McCord and McCourt are anglicized versions of older surnames.
At that time in America, and into the next century, prejudice against the Irish was extreme. McCourt is mentioned in most history books as an "Irish" surname and McCord is listed as a "Scots" name; albeit the two seem to be related. Some genealogy books refer to the two surnames as synonymous.
I am trying to figure out if my direct family line was originally McCourt or McCord. I do know that they spoke Irish when they arrived in the colonies abt 1720. I believe that mine were originally McCords from the Scottish Lowlands, but had lived in No. Ireland for many generations.
I will keep the information you sent me about your McCourts and will look at the Stonyford history, even if they are not directly related, it is good information for those for whom might be. thank you for your response. I appreciate that, kathleen McCord