The Mixolydian setting is similar to what I heard some years ago from Laurence Nugent, who of course added a whole lot of his wild syncopated variations, because he can.
Hearing Tony himself play it last night (thanks to Dean Karres, http://www.pipers-hut.com), I was surprised to find it’s minor. The following is simplified considerably from track 6 on his CD of the same name: