"Letters of Administration of the personal estate of Andrew Fullerton late of Drumnacross County Tyrone Farmer who died 12 April 1887 at same place were granted at Armagh to Mary Fullerton of Drumnacross the Widow."
You can't order the Will because there
never was a Will (administration means that Mary, his widow, applied for permission to legally sort out his estate. The 'address' for Andrew & Mary in 1887 was Drumnacross (the townland).
Possible Will Extract for Mary (1904)- you can view the details from Will Book on PRONI's site.
"Probate of the Will of Mary Fullerton late of Drumnacross County Tyrone Widow who died 6 May 1904 granted at Armagh to Robert Fullerton Farmer."
Mary Fullerton was a widow, had sons Andrew, John, Robert, Orr, William.
Son Orr Fullerton?
"Probate of the Will of Orr Fullerton late of Drumnacross County Tyrone Farmer who died 15 February 1922 granted at Londonderry to John Bole and John Ferson Farmers Effects £68 12s. 6d."
If you search for Fullerton as surname and Drumnacross in full abstract box you will see other family details-
http://applications.proni.gov.uk/DCAL_PRONI_WillsCalendar/WillsSearch.aspx1901 census- Mary Fullerton & some of her sons-
www.census.nationalarchives.ie/pages/1901/Tyrone/Oaklands/Drumnacross_Lower/1729391Andrew Fullerton who died in 1887-
https://familysearch.org/ark:/61903/1:1:FT49-B6J