Hi Ed. Lucky to be going to Kilrush this year! I wanted to let you know that Kilrush has a wonderful local historical society. They are very active on Facebook under "Kilrush Local History Group". I bet if you post there as well you may get some good information. Also if you have not had a chance to check it out, try the Clare library online. They have a fabulous amount of genealogy data transcribed. http://www.clarelibrary.ie/.
I live in the US but my own family is from Kilrush. A long line of Fennell, Cushen, Comyn, McNamara among others. My second great grandmother was an O'Connell but we don't have much more than that. Could be that we are related somewhere way back when.
You will love Kilrush if you have not been before. I've been going back and forth since I was about 5. I love it there.
Good luck in your research!