I am feeling so embarrassed!!

Today putting all the census and BMD's for this family in order. I happened to look at a marriage certificate and discovered that all your hard work on this thread was in vain. As were the costs involved in purchasing the relevant documents from SP. And it is all my fault!
The quote below is from the very first message:
"I feel this is an impossible search! How do you search for a James Mc..........
when there are so many variations? This name is worse than Smith in England at least there are only two versions of that name.
If there is an expert on Mc......'s out there the person I am looking for is James Mclellan married in the parish of Glasserton in the county of Wigtownshire at a place called Craigdan? His name is spelt McClelland but his daughter's birth certificate says McLellan. I am wanting to find his birth."
McLellan was not the problem! The father's name is JOHN McLelland and the wife is Mary Stewart on the daughter's marriage certificate. I have been through the IGI for Ayrshire, every parish available, but the latest they reach 1875.
I think I have the Marriage cert for her parents which shows:
John McClumpha McClelland (Ploughman and living at Barrhill or Barnhill) and Mary Stewart (20 and living at Knockdolian, Colmwell?) married 25 November 1890 in the parish of Girvan in the county of Ayr. But I notice a C before Lelland!
John is 21 and his father is William McClelland (another ploughman) and his mother is Mary McClumpha
Witnesses: John Murray and Frances Milligan
Joseph Ferguson married Evelyn McLelland 18 Jul 1913 at Burnton, Dalrymple in the county of Ayr.
His parents were John (actually James) Ferguson and Christina Shea
Her parents were JOHN McLelland (Ploughman) and Mary Stewart
Witnesses Isabella McLelland and John Kirkwood.
There are 2 births for an Evelyn McLellan and both have the parents that we followed in error. They are in 1892 and 1890.
Please can someone help me find the answer to this problem?
Regards,
Abiam