Hi John,
I don't know if you have your fathers Birth Certificate, if you want I can send a copy, but he was born in 10 West Seaside, Prestonpans. If you put that on Google maps you get a great view of Cockenzie Power station at one side, and Edinburgh and Arthurs Seat on the other side, and of course, the Firth of Forth.
Your grandfather, was your namesake, John Donaldson Harkess and grandmother Alison Drysdale McLelland, who were married on 31st Dec 1908 at Prestonpans.
Tom