Sandy - a small correction: Tom and Bob's duet of this song, later released on The Perfect High album, was not recorded at the Earl, but at Charlotte's Web in Rockford, on 1st August 1979. The full concert containing the song is at Snapshotmusic website. The night was a double bill Bob and Tom:

Bob Gibson 1st Set

Cuckoo Again
A Gallon of Gas
Heavenly Choir
Just a Thing I Do (Kathy O'Grady's Song)
Mendocino Desperados
Rock Me Sweet Jesus
Bein' on the Road
Army of Children [with Anne Hills]
Leaving for the Last Time [with Anne Hills]
The Perfect High (Baba Fats)
Piece of Ass

Tom Paxton 1st Set

Life
I Can't Help But Wonder Where I'm Bound
Gas Line Romance
When Annie Took Me Home
Has Annie Been in Tonight?
Hand Me Down My Jogging Shoes
Hush Old Man
The Love of Loving You
Bad Old Days
All Clear in Harrisburg
Feed the Children
My Favourite Spring
Let the Sunshine [with Jim Post]
Don't Forget Your Waitress
The Last Thing on My Mind [with Jim Post]

Bob Gibson 2nd Set

I Like Your Song
Easy Now
I'd Love to Love You (But Your Time Is Just a Little Off)
Heavenly Choir
Bein' on the Road
What You Gonna Do About Love [with Anne Hills]
Army of Children [with Anne Hills]
Leaving for the Last Time [with Anne Hills]
Cuckoo Again

Bob Gibson and Tom Paxton

Outlaw
Box of Candy and a Piece of Fruit

Tom Paxton 2nd Set

Saturday Night
That's The Way It Seems to Me
Home to Me Is Anywhere You Are
A Golf Ball Often Has a Mind of Its Own
Bad Old Days
Did You Hear John Hurt?
My Favourite Spring
When Annie Took Me Home
Ramblin' Boy