In Parallel Lives , Dick Porter and Kris Needs' biography of Blondie, there is a reference to the T-shirt concert, on October 23, 1976:
With the album scheduled for Private Stock in December, Blondie continued their live act with shows at the Cuando Gym on Seventh Avenue (where they took the stage at 2:30 and made such an impression that everyone assumed they were the headliners, leaving the real headliners, The Dictators, without an audience), Max's (with the Tuff Darts), and CBGB's. Reflecting on the Cuando gig, Debbie recalled, "That was the first time I felt really good after playing. Super cool. Maybe because that was the first real stage we played on. Afterward, the Dictators and the promoters got mad at us."
Miriam Linna (later drummer for The Cramps and A-Bones) was also there and shortly afterwards wrote in an article dedicated to the Dictators: I love Dick Manitoba because he shook my hand when I knocked out a crazy drunk at the Cuando Gym rock'n'roll festival last October, and because sometimes he wears a white shirt and a black vest that look great on him.
Dee Dee Ramone didn't miss it either: Blondie was in great shape that night, and I had a lot of fun. Deborah Harry, wearing the shortest miniskirt I've ever seen, looked stunning. The guys crowded under the stage to look at her white panties.