Looking for the same thing. I think this may help.
Description of Ushlawrcoed,
http://www.visionofbritain.org.uk/place/25176My interpretation is that West of Nantybwch to Argoed is considered Ushlawrcoed.
Read the Enumeration Page of the 1841 Census, "Malthouse Row and George Street in Tredegar".
Here are the coordinates for George Street, "51° 43.274'N, 3° 14.580'W"
1888 Map of New Tredegar,
https://historicplacenames.rcahmw.gov.uk/placenames/mapFrom the 1888 map, the row of houses at the top of Commercial Street I believe are "Malthouse Row". Or Commercial Street was Malthouse Row in 1841.
Here are the coordinates for "Malthouse Row", 51° 43.409'N, 3° 14.702'W