Ray, let me know where he fits in and I’ll see what I can uncover.But if you mean the Donald Menzies who married Rachel Cameron in Dull on 16 Mar 1749, he would be the Donald baptised 17 Apr 1718 to Duncan Menzies & wife Katrin, I feel.
I had looked at them because they had a son named Duncan baptised 6 May 1750. But on reflection that looks a few years too young. Our Duncan’s wife Catherine McDougall was born before 1748 when the Fortingall parish registers commenced. So likely our Duncan also. Plus I have nothing that placed our Duncan in Dull.