We have come across this before. Ar fud is CO. Ar fuid and ar fuaid are Cork Irish. But what is the difference. PUL explains in his extraordinary Notes on Irish Words and Usages:

ar fuaid is used when the space contemplated is extensive, eg ar fuaid na dútha, ar fuaid na paróiste. The form ar fuid is preferred when the space is small, eg ar fuid an tighe, ar fuid an bhaill.

Interesting.

Sounds like a treasure trove, that book! Hope it flows into your proposed dictionary.

It is. it is 117 pages of comments on words and phrases followed by a further 36 pages of grammatical comments (eg on tá vs. the copula and such like)

I was just looking at his treatment of fiche. he says:

fiche blian = a score of years
fiche bliain = 20 years

and that both are good Irish.