Found pic and was looking when I saw what appears to be a 1971 or 1972 Mustang in the race starting grid. I sure looks like a 24 hour endurance series race. If anyone can offer more info - please do.
My first thought was it was a European race because most of the cars seem to be European. I see one 69 Mustang up front but all the others Opel, Ford Capri, Audi Coupes, Ford Escorts, BMWs and lots of Alfa Romeos.
I've done a bit more digging. That picture was from Spa in 1974. It was known as the Inotage Mobel Alvisse Ford Mustang and driven by Nicolas Koob and Aloyse Kridel.
The Mustang retired after the 7th hour with head gasket failure.
It wasn't the slowest car out there but was over 40 seconds a lap slower than the fastest car. They qualified 35th out of 58 cars. The 69 Mustang was the #1 qualifier but was a DNF :-(
I love the old racing footage, especially the CanAm, TransAm or V8 supercar stuff. Unfortunately, everyone seems to think they are race drivers...with swing axles.