As your subject suggests, there are many variations on the spelling of McGoohan. I am researching the McGeown branch that came from Derrynoose, Keady, Co. Armagh to West Lothian in 1890 or thereabouts. The parish records from Keady show surnames as McGeough, McGeon, and McGone although all children definitely have the same parents in Stephen McGeown and Mary Kirk; my guess is that the parents had no idea how to spell their own surname and the entries to the parish registers are based on how the name sounded when spoken.
Interestingly, of those who came over, John (11 October 1857) and his brother Thomas (25 May 1862) lived with their sister Sarah (15 February 1860) who became Sarah Donoghue and who lived at 98 Greendykes Road; that detail comes from the 1891 census. Their siblings were Ellen (29 April 1865), Margaret (21 July 1867), Catherine (13 February 1870), Stephen Patrick (24 March 1872), Henry (25 August 1874), and James (14 July 1878).
It may be that the McGeowns that I am looking at are related to your McGoohans who seem to have come to Scotland in the earlier years of the shale oil boom.
Have a look at
http://www.scottishmining.co.uk/130.html for an excerpt from the 1918 Royal Commission Report on Housing that describes housing in Greendykes Road. The report also has descriptions of Niddire (Winchburgh) and other local housing.