Lemons (the series this car has raced in) are real sticklers about safety items such as cages. I also agree with freebeards description of the wing as that gap leads me to believe that it is not just a trunk extension.
I saw a 'socer-mom' themed Dodge [turbo-]Caravan at a show-and-shine. They had done pretty well as I recall, but they'd had to cut patches out of the roof and re-rivet them so the tech inspectors could see the welds on the roll cage.