Bless you Ray for looking up that info for me.It looks VERY good at this point.
What you have found about James Harris is pretty much what I have gathered too.
However I could not find him in either 81 or 91 as you say.I will definitely
look into this 1891 family you have found.Another problem was that I did not know what the RD was for Llandysul.I did try Google.Newcastle Emlyn will help a bit. I know too that giving conflicting places of birth on a census may indicate an oow birth.
(I have one of my own on the 1881 born at Lindos Forest!! Sounds more like a football club to me)

We do know that the man buried in 1955 in Brynithel cemetery,Abertillery is my correct man since his daughter (Sarah E Powis) was the Informant on the death cert. Here again though he was wrongly named as James George Harris age 77 (1878) grave #235-1-B.As you see the age does not mesh with the 1873 birthdate.(Though I know death info can be iffy at the best of times)
(Did you know that a gravestone is the only object that can stand upright and lie on it's face at the same time??)

James was also said to have been a boxer and at some time, fought Victor McLaglen the screen actor/boxer.However a list of his fights does not show anything.
He was also named wrongly as James George Harris born 20 May 1873 at Pontarddulais, father James a shipwright in the Family Bible.
We do have the birth cert for the correct man of that name and dob born at Aberdyberthy Street, Swansea 20 May 1873 to JH and Mary nee Parker and the marriage cert to Eliz Thomas,1905 also confirms this family as that of the real JGH.
Can't find this man in 1901 though.He appears nicely on all other census.In 1891 he is a labourer but in 1911 he becomes a Publisher's Manager.I feel he was perhaps in the Army in 1901 and possibly in the Boer War at that time? Perhaps an Army career helped him up in life.
Family word of mouth is said to have indicated that my JH joined the Army underage but that he was brought back by the family to live with a brother.Could he and the real Harris have been buddies in the Army...my JH going AWOL more or less quite soon but the real man staying on until discharge? AWOL would explain a false name etc and not wanting to be caught.
Again....many, many thanks for going to the trouble of searching for this man.
Roger