I am trying to distinguish possible Ty Ucha(f)s - a very common name.
Ty Ucha,Tyfos is likely to be the one close to Llandrillo as these properties form a sort of arc near there
Tyfos,Hendwr,Ty Uchaf,Moel is y Coedwig,Llechwedd,Garthian
However,there is a Ty Ucha,close to Plas Adda,which is more likely to be described as Gwyddelwern.
It feels like your various threads are in here somewhere.
Regards
Roger