Hello Simonsez
John William Scott Harrison is my great grandfather too, which means my mother (daughter of Frank Robson Harrison his eldest son I think) and one of your parents are cousins! I still remember his wife Mary my great grandmother who died at 95 - used to go and visit her in Roker as a child.
I have a few more generations of the Harrison line, and a picture of John William Scott Harrison and his children, and other family memorabilia. Don't want to send these if you already have them, but do get in touch and lets compare notes.
Ian