Gary's live version of London Homesick Blues on Jerry Jeff's Viva Terlingua album is my favorite.
It was the promo party for the Los Gonzo band's first album. About all I remember is sharing a bottle of mescal with an old wino. I didn't know he was Willie Nelson until the next evening when the lady who lived there thanked me for taking care of his girlfriend. But that was Austin in the 70s.