I have tried most of the mainstream sites, but this is a bit obscure.
The song is based around an allegedly true "sick note" from a building site worker to his boss.
I can remember several verse's but there are many. Bit of a long shot, but will post a verse, if anyone knows the whole thing please post.
"Dear sir I write this note today to tell you of my plight, for at the time of writing I am not a pretty sight, me body is all black and blue my face a deathly grey.....I write to say why paddy's not at work today"
I know more, but this should be enough to jog the old grey matter!