Thanks so much all of you for your interest and local knowledge.

I think
dwsi's link is extremely helpful...........and the Llys Helig Drive (I've read the legend about Prince Helig) looks extremely likely. Ironically we passed by there on our coach tour recently and were told Cliff Richard was a former resident!!

Only one thing troubles me and that is whilst the extension on the left of the photo and the two large gables match, the two smaller dormers in the roof are missing. However, if the property subsequently has been re-roofed, as would be reasonable in this exposed position and with the age of the structure, they might have been dispensed with. Sadly the definition on Google Earth is rather poor and Streetview makes me seasick!
My friend has read your comments and is very excited to track things down after all these years. She is hoping to register to comment further but I believe her computer is poorly and she likely has to wait for a repair.
But again, many thanks to you all.

Olden.