I've been humming this one, on and off (off key, espec!) since it was mentioned, and find I've come up with a few more words:-

If you see the undertaker
Or the young man from the Pru
Drink a pint with what's left over
Now I'll say "good-bye" to you.

(The Bells of hell etc etc)

I don't know if theses are the original verse, or whether they are the invention of Behan - any ideas?