Have you tried the death record for David Morrison who d 1865 in Old Kilpatrick, Dunbarton? He could be your man, although he died quite young around age 34. Dunbartonshire is located very close to Glasgow, as you thought he probably died in that area. Also, it would be a good idea to check the death record of his widow; namely, Mary Jane Morrison, other surname Newlands, who d 1903 in Govan, Glasgow, as there may be information relating to her husband and family that could be helpful. It would also be good when giving out the information that you may already have, to give FULL details, such as the date AND location of their marriage as you seem to have that record. In other words, tell us as completely as possible what you already know, as that will help those of us who are trying to help you and prevent duplication of effort! Checking possible Census returns will also yield you information on children, and tell you where the family lived at particular times, and may even suggest the place where they died.