I believe your talking about the Orange #24 of Carroll Cheek. You pretty much decribed it to a tee.
Its the same car (I believe) in the post #97 marked as number 21. It was the only orange car in this area at that time. Shortly after that pic was taken Carroll fell in love with the orange Foyt was using at the time and repainted the car with it. Being friends with Foyt he spent a bit of time around that color. Most beautiful orange.....actual code name was Foyt Red
Does anybody remember Wayne McNally's purple rear engine car? Boy that was a beauty also.