I believe Donald Whytes' source for Rory McLeod and Catherine McCuaig was page 450 of the newer McLeod Book (1793-1993) (MB). I don't know the author or contributor of this genealogy but I doubt its accuracy.
The descendants of Roderick Òg and Catherine McCuaig who are listed on page 451 are completely different from the ones listed on page 373 for the same couple. The listing on page 373 are my ancestors and this information was contributed to the book by a cousin of mine, Clarence Xavier Dodd, so it has a certain credibility from my perspective. According to this version the family lived at 22W.6 Lochiel for much of their lives.
The gravestone of Roderick Òg has that he was 71 when he died in 1868 so his calculated year of birth would be about 1797.
However, the 1851 Census of Lochiel, page 107 Line 48 has Roderick McLeod, age 60 with a birth year of 1791 and a birth place of Scotland. His wife, Catherine listed on Line 49 was 42 years for a calculated YOB of 1809. This corresponds to the birth and baptismal record from St Andrews Presbyterian in Williamstown which states she was born on 22 Feb 1809. Both her Baptismal record and the census state she was born in Canada which differs from a birth place of Scotland which appears on page 451 of the MB.
Although it was unusual, the enumerator for the 1851 census listed the Lot and Concessions where the families lived and Roderick Òg and Catherine and family were living at 17.6 Lochiel, the same farm as a family of McCuaigs, presumably closely related to Catherine.
Catherine's birth record lists her parents as Peter McCuaig and Nelly (Helen) Fraser. On page 451 of MB, it states that her father was Patrick Post McCuaig and that the family had emigrated from Scotland in 1818 which seems unlikely if she was baptised in Williamsown in 1809.
I knew from the MB that the other Roderick McLeod had settled on Lot 30.7 but did not know he married Mary McLeod and had 6 children. Does this genealogy appear in the MB? Was one of their sons Roderick Òg? You say they moved to 24.6 which is close to 22W.6 where Clarence Xavier says Roderick Òg and Catherine McCuaig lived. By 1851 Lot 24.6 was occupied by McPhees.
I hope you can provide more details or a source for Roderick and Mary and their 6 children.
I appreciate you interest and help,