I saw the late Fred Holstein play it years ago in G. From memory, I think he played it in G and think it progress to a D with the F# in the bass, followed by and F chord,than it went back to the standard chords that go with the key of G. (C, D, Am) sorry I can't tell you the order without having a guitar in hand and the words out there (which I don't know). If you try the G chord with the third fret of the B string fingered, but the high E string open, you can get the first bit of the melody, for an introduction.

I saw Michael play it years later with a more elaborate arrangement, though I think it was still in G. Good luck.