Hi Allan,
My first posting...
We may have a connection. My ggg was Hugh Fulton born approx 1828. I found his Scotland to NY bound ship record from 1869. He was listed as a weaver with wife, Jane, children Mary, Hugh and William. The family are in the 1870 NY census. I found a newspaper article in which his sons Hugh(my gg) and Billy visited family in Kilbarchan where they lived as boys. I researched the Scottish census records and found the family on High Barholm St in 1861. The closest fit for the 1841 census was the Hugh Fulton family on Ewing St, up the road from Barholm St. From there I speculated that Hugh married to Mary McNeil was my gggg, the same as you. If all these assumptions pan out, a big if(?), your ggg Joseph and my ggg Hugh were brothers. Would love to review what you have if possible.
Thanks very much for posting your info.
Hen