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I looked in the Tithe listings for the late 1820s and also the 1855 Griffiths Valuation head of household listing for Kiltrustan and there was no location called Ballymulconry and there were no Mulconrys listed in the parish. There were Conrys listed in the parish in 1855. http://www.failteromhat.com/griffiths/roscommon/kiltrustan.htm I further checked on this Irish Times web site
http://www.irishtimes.com/ancestor/surname/ and the only Mulconrys listed were in Co. Clare with one additional family in Co. Tipperary.
In the 1901 census, all the Mulconrys listed were in Clare with one person in Co. Galway.
Let me know if you have additional info.