Welcome to Rootschat 
Presumably you know who his parents were if he has a Scottish marriage certificate? Have you found evidence of them in Scotland?
Is there a chance he was not born in Scotland?
Hi avm228,
Dad was not married in Scotland but in Bridgetown, Barbados in 1943. On the marriage Cert it gives his father's name as John Patrick but no mother's name. We cannot find a trace of John Patrick either! There is a distinct possibility that he was born in Ireland but again there is no trace.
I have a number of threads on this site about my search for Dad, and indeed on many war based sites too. Probaby the best two threads for information on here are:
Family History Beginners Board / Re: Not so much a brick wall s a brick mountain
World War Two / Hunting Wartime Records
These should fill the gaps and give you everything I do know,both proven and hypthosis.
Thanks for you time