I suspect that the townland that the McNeills lived in was Lisnagunogue Lower.
The 1803 Agricultural census on Bill McAfee?s site lists a William McNeill farming in Lisnagunoge.
The tithe applotment records for 1824 list 3 McNeill farms in that townland (Charles, Daniel & Elizabeth who was probably a widow):
Griffiths Valuation for 1861 lists a James McNeil with what looks to be a farm, plus a house and garden, a house forge and garden and 21 acres (plots 10l, 10p and 21) there, and an Aeneas McNeill next door farming 18 acres (plot 17).
Those farms today are just off the Whitepark Rd, on the north coast of Co Antrim.
There was still 1 McNeill family there in 1901:
And in 1911:
Family were Presbyterian. Nearest Presbyterian churches would be Bushmills, Mosside and Toberdoney.
Some probate abstracts for that family, taken from the PRONI website:
McNeill Alexander of Lisnagunogue Bushmills county Antrim farm labourer died 7 October 1939 at the Mental Hospital Antrim county Antrim Administration (limited) Belfast 7 November to Samuel James McNeill farmer. Effects ?238 17s. 6d.
McNeill Mary of Lisnagunogue Bushmills county Antrim spinster died 11 December 1956 at Runkerry House Bushmills county Antrim Probate Belfast 22 January to John Charles Faulkner presbyterian clergyman and Jennie Wallace spinster. Effects ?1678 3s. 8d.
McNeill Rose of Lisnagunogue Lower county Antrim widow died 30 September 1924 Administration Belfast 20 March to James McNeill carpenter. Effects ?50.
(The probate files themselves are held in PRONI in paper format).