I don't yet have more information on SNP L513 and won't until I find out more from one of the FTDNA group administrators. I mentioned an Italian with the P66+ SNP and that there were differences in our test results. He was tested by Ethno-Ancestry and the group administrator needs his results on DYS 617,
406S1 and 640. Meanwhile, Jim McKown and I were not tested on markers that the Italian was: Dys461,462, 463, 434, and 435.
I have asked the administrator if this means that the Italian should be tested by FTDNA on threee markers or that Jim and I should be tested by Ethno-Ancestry on five markers. Neither approach sounds feasible to me. In fact, the Italian, if interested, should be retested to 67 markers by FTDNA because there is a good chance that he may be descended from Cuchonnaght Maguire who died in Genoa, Italy,
in 1608. I hope for all our sakes that he is as interested in his ancestral surname as he is in his ethnicity.
I mentioned two postings ago about three McCowns being classified as Ua Flaithbeartaigh although we don't match each other above 12 markers. It turns out that while the above name in Gaelic was applied to an historical O'Flaherty or O'Lafferty, that there was also a Maguire in the chiefly line with the given name of Flaithbeartaigh, so that name could conceivably apply to McCowns of Maguire descent.