I had a feeling there'd be one around Garston/Speke. I stopped looking when I found an upturned kerb-stone, facing the old fire-station.
I'll have to check the 3 metal plates in Ullet Road, as I must have missed one in the fog the other day. There should be 2 on the Princes' Park side of the road that state 'Liverpool' and one on the other side that states 'Toxteth Park'.