Stella's parents house is 27 Rhondda Terrace.
Check it out from the front door - which we never used in my days in 20 Rhondda Tce - we always used the back door. Google shows it sparkling white as per the show.
The 'new' houses I think are Rhondda Fechan Farm development off Rhondda Road.
The land used to be owned by the Evans brothers - Evans the Milk and Evans the Bookie.
I have not been able to locate where the post office/shop is, as yet, but will keep looking.
The other one I have been stuck on is the street that they used for filming the funeral cortege of Dick the Kick. They used a horse-drawn hearse and when they walked behind it, to their left- there were trees/hedges behind a newly green-painted metal fence.
I think that this may have been alocation shot as it would be simpler to take the cast to the hearse than to transport the carriage and horse to Ferndale. I will persevere.