Thanks Wyndham but that is the wrong one. The version I am after is the traditional Irish tune, later adopted by the US 7th Cavalry. I have worked something out for the verse, though I am sure the chorus is a little different, but I am not sure if this is correct:
GARRY OWEN
G.........................Em
Let Bacchus' sons be not dismayed
.....G.......................D7
But join with me, each jovial blade
.........G.......................Em
Come, drink and sing and lend your aid
....G.....................D7......G
To help me with the chorus:
CHORUS: Instead of spa, we'll drink brown ale
And pay the reckoning on the nail;
No man for debt shall go to jail
From Garryowen in glory.
We'll beat the bailiffs out of fun,
We'll make the mayor and sheriffs run
We are the boys no man dares dun
If he regards a whole skin.
Our hearts so stout have got us fame
For soon 'tis known from whence we came
Where'er we go they fear the name
Of Garryowen in glory.
Added later:
We can dare or we can do
United men and brothers too
Their gallant footsteps to pursue
And change our nation's story.
And when the mighty day comes round
We still shall hear their voices sound
Our clans shall roar along the ground
For Garryowen in glory.
We'll emulate their high renown
To strike our false oppressor down
And stir the old triumphant sound
Of Garryowen in glory.
Here's Hollywood's version of how Custer adopted it:
Garry Owen & the US 7th Cavalry 
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