The cross harp version is the easiest, imo:
http://www.harptabs.com/song.php?ID=16190
And the straight harp isn't bad either:
http://www.harptabs.com/song.php?ID=16189
But here it is in 4th position if you'd rather have a challenge.
2 -2’ 2 -3” -3”-3” -3” 2 -2’-2’ -3” -3” -3”
I-I could ride around the world in an old oxcart
2 -3”-3” -3” -3”-3”2 -2’ 2 -2 2 -2’ 2
And never let another gi-rl thri-ll my heart
CHORUS:
2 -2’ 2 -3”-3” -3”-2’ -3” -2’
Ain't tha-t loving yo-u baby? (x3)
-3” -3” -3” 2 -2’ -3”
Ain't that loving you so?
2 -2’ 2 -3” -3”-3”-3” 2 2 -2’-2’ -3” -3” -3”
I-I could meet a hundred girls and have-uh loads of fun
2 -3”-3” -3”-3” -3” 2 -2’ -2 2 -2’ 2
My huggin' and my kissin' belongs to just one
(REPEAT CHORUS)
2 -2’ 2 -3”-3” -3” 2 -2’ -2’ -3”-3” -3”
I-f you gave me nine lives like a tommy cat
2 -3” -3” -3” -3”-3” 2 -2’2 -2 2 -2’ 2
I'd give 'em all to you and never ta-ke one back
(REPEAT CHORUS)
2 -2’ 2 -3”-3” -3”-3” 2 -2’-2’ -3”-3” -3” -3”
I'm putting on my Sunday suit and I’m goin' downtown
2 -3 2 -3”-3” -3” -3” 2 -2’ 2 -2 2 -2’ 2
But I’ll be kissin' your lips before the su-n goes down
2 -2’ 2 -3”-3” -3”-2’ -3” -2’
Ain't tha-t loving yo-u baby? (x2)
2 -2’ 2 -3 -3 -3”’ 2 -2’
Ain't tha-t loving you baby?
4 -3 -3 -3” -3” -3”
Ain't that loving you so?