Well if I tell you it was one of 13 Historic Counties and was bordered by Montgomeryshire, Brecknockshire, and Cardiganshire and (Shropshire and Herefordshire) you should be able to work it out!
Alternatively go to oldclassiccar.co.uk and look up "FO"

Regards Neil
PS
The "County" has also featured on POTD at least once......This nice old garage is in one of its main towns.