Hi Kim,
My 2nd great grandmother was MaryAnn Madigan b cir 1824, probably near Kilcolman, Co Limerick, so I'm aware that the Madigan surname is very common in Co Limerick.
I checked a couple local history books that I have and did not find any Madigan/Kennelly connections. Other spellings you may want to consider are: Kennelleay and Kinnaley. Madigan also appears to be sometimes written "Manion" and "Mangan."
Do you own the Kim Elliott tree at Ancestry.com? I don't see any other Ancestry.com trees that have any more info than you do.
However, at FamilySearch.org, I found a Pensioner rcd for a Michael Madigan that was born in 1828 in Limerick. The rcd is available for viewing at Find My Past. I had trouble getting into that site, so I don't know what other info may be on the rcd.
Did Michael remain in Ireland? I found a death rcd for a Michael Madigan b 1828 in Limerick who died in Rathkeale in Apr-Jun 1898.
There is quite a bit of info about the Kennelley's and Madigan's in a couple local history books. One is Poverty to Promise: The Monteagle Emigrants 1838-58 by Chris O'Mahoney and Valerie Thompson; the other is a follow-up book, West Limerick Families Abroad by Kate Press and Valerie Thompson. Both of these books follow the Kennelly and Madigan families of West Limerick (the area you're searching) to Australia. Again, while there are plenty of Kennelly and Madigan families listed in these books, I could find no records that had a Madigan/Kennelly connection, at least by marriage. I did see some rcds where the mother-in-laws were one of the two surnames.
I checked the Irish phone book. There is one Madigan in Shanagolden, Mary. I did not see any Kennelly (or variant) entries.
Also, you may be aware that the Irish Catholic Church rcds are now online (and browseable - there are no indexes yet) at the Irish National Library. http://registers.nli.ie/
I will send an email to the IrelandXO team in Shanagolden and see if there might be other Madigan or Kennelly families living in the area.
If you have ohter questions, please don't hesitate to reply.
Best wishes,
Patti Hacht
Shanagolden & Kilcolman IrelandXO Parish Liaison