Thankyou William thats a helpful thought and possible. Although there is some consistency with the birthplace on the census records.
I think that in North Wales the records are split between various research centres across the region? I am trying to continue the extensive work my mum did and would like to complete this one puzzle for her as she is unable for the most part to finish what she started (although do we ever 'finish' what we have started as researchers?!).