I remember only parts of the chorus. It was one bass voice starting out:
"A gone gone gone, she been gone so long, she been gone gone gone, she been gone so long"
Then a tenor comes over the second time with:
A gone gone gone, well I wonder if I'll ever see her again...."
And then some other tenor parts added too.
And then I think it comes to a unifying part where all the voices sing at the same time:
"My Girl! She is the best to me!.....My Girl!
That's all I got. If it helps, I heard it on a college radio station in Binghamton, NY. TIA