In November of 1966 a few 1967 RS/SS Camaro convertibles were used to pull floats in the Macy's Thanksgiving Day Parade in New York City. Not sure what kind of hitch was used but in an old thread on the Camaro Pace Car site about these cars Geoff Smith stated, "There is a GM memo somewhere commenting on the Chevy cars to be used here. From memory there was about 20 Camaros and a hand full of Impalas too." If that's the case then GM must have okayed it and provided the cars with trailer hitches or perhaps instructed a local dealer to add aftermarket hitches.
The first picture is part of an article that appeared in the September 2013 edition of Racer Magazine on the 1966 racing movie entitled Grand Prix. The caption for this picture states, "Prior to its Dec. 1966 opening, Grand Prix takes center stage at the Macy's Thanksgiving Parade in New York. Yes, that is a somewhat bemused '66 Formula 1 World Champion Jack Brabham on the float." This float had to be pretty heavy with not only the heft of the float itself but the weight of at least two Formula One cars and all the people standing on it.
The second is from Youtube footage of the parade that can be seen here:
http://www.youtube.com/watch?v...TQLHuWhqFt6q--N0IcK7 Two different Camaros can be seen towing floats. I took a picture of the Camaro towing the Grand Prix float that can be seen at 1:50 in the footage.
The third picture was provided by the aforementioned Geoff Smith in the Camaro Pace Car site thread