It would be 'Bhí an t-ádh dearg orainn' in Irish.
The word 'luck' is in English not Irish Gaelic.
an t-ádh dearg
In Irish it is Bhí an t-ádh dearg ort.
ádh (pronounced 'aw')
In Irish it's "ádh"
ádh na nGael
I have always thought this was an American expression, but I am not certain
ádh. Pronounced: aah
Scottish Gaelic: Beir buaidh! (best of luck, I hope you succeed!)Irish Gaelic: Go n-éirí go geal leis. (The best of luck to him.)
In Irish it's "dheamhan mí-ádh"
ádh (m1) - (good luck to you is - ádh mór ort!)
Go raibh an t-ádh dearg oraibh.(plural)