In any endeavor, it helps to know the right people. In this search for my line of McCowns, I am most fortunate to have Barry McCain, firstname.lastname@example.org, administrator of the FTDNA Ulster Heritage Group, http://www.ulsterheritage.com, in my corner and hopefully Dr. William Roulston, Chief of Research, ULster Historical Foundation. The latter is dependent on Dr. Roulston's evaluation of my Y-DNA results and whether or not we have enough data to proceed. Dr. Roulston received the data by email today and I am on pins and needles awaiting his analysis.
Barry McCain has pinned down Enniskillen, Fermanagh, as the most likely loacaton of my McCowns no longer ago than 1600AD. He believes that we are paternally related to the Maguire Clan and that the MacEoin/McCowns are in fact part of the Clan. This is most encouraging.