Hi Andrew,
I replied to this message in 2006. Was wondering if you have had any luck tracing your Manchester Coghlans.
There has been a lot of work done on my Coghlan family especially by a relative, Alan Clancy. Another person who replied to you from Australia, Ann Fisher, also has links to my family. It's just possible your ancestors are connected with ours. Please get in touch with one of us if you need any help.