Well, I won't vouch for the quality of this, but it's all I have time for. I found it in this PDF songbook. It's also in a songbook at Immortalia.com.

THE LAST LONG MILE

1.
Oh, the put me in the Army and they handed me a pack,
They took away my nice new clothes and dolled me up in tack,
They marched me twenty miles a day to fit me for the war,
I didn't miss the first nineteen, but the last one made me sore.

Chorus
Oh, it's not the pack that you carry on your back,
Nor the Springfield on your shoulder,
Nor the five inch crust of coffee colored dust
That makes you feel your limbs are growing older.
And its not the hike on the hard turnpike, that wipes away your smile;
Nor the socks of sisters that raise the blooming blisters,
It's the last long mile!

2.
Some day they'll send us over they'll put us in the trench,
Taking pop shots at the Fritzes with the Tommys and the French,
And someday we'll be marching through a town across the Rhine
And then you bet we'll all forget these mournful words of mine.
Chorus

3.
Oh, they put us on the Salt Springs hike and handed us a pack,
They took away our nice new clothes and dolled us up in tack,
marched us twenty miles a day to fit us for the chore,
We didn't mind the first nineteen, but the last one made us sore.
Chorus