Dear Ray,
I don't have much more information than you do. My info. says that James Elgin was born in 1760 in county Derry, Ireland, and died 20 Dec 1837 in Armstrong Co, PA. Buried at St. Thomas Cemetery, Plum Cr, Twp, Armstrong Co., PA. His wife's name is spelled Ray in my records.
I have a lot on his siblings, and William's siblings, as you probably do, but no more than what you have on William and his dau. Nancy, and no other children are listed other than Nancy. My info. gives William's death as 10 April 1833
I have that Margaret McIntosh was born in 1809 in PA, and they were married 22April 1830. My source for these is someone else's genealogy (and her line is similar to mine). I have various sources for the rest of the Elgins.
I am descended from Daniel (1774-1844, married Mary Patton), the older brother of the James who (I think?) was born in 1760.
Sincerely,
Julie Gibson