getting that far back has its own headaches.
from
http://griffiths.askaboutireland.ie/gv4/gv say datewise late 1850s/early 1860s
Occupier Surname Occupier Forename Placename County Parish Details Original Page Map
McAlister Esther Glaskerbeg, East Down Aghaderg
McAlister Esther Glaskerbeg, East Down Aghaderg
McAlister David Glaskerbeg, West Down Aghaderg
McAlister John Glaskermore Down Aghaderg
McAlister Joseph Glaskermore Down Aghaderg
McAlister Samuel Glaskermore Down Aghaderg
McAlister William Derrydrummuck Down Aghaderg
McAlister George Derrydrummuck Down Aghaderg
McAlister Samuel Derrydrummuck Down Aghaderg
McAlister Mary Derrydrummuck Down Aghaderg
McAlister Esther Derrydrummuck Down Aghaderg
McAlister Esther Shankill Down Aghaderg
McAllister Jonathan Ballynaskeagh Down Aghaderg
Have you used Ros Davies Co Down website, for the surnames and variants
its also good for her church records that survive
In the Linenhall Library is a manuscript for McAllister in volume 92 of the Blackwood collection, this may not be your family line at all, but..........
Must rush on, and good luck sorting the two lines and their first cousins
jim