Back in the 90s, my buddy drag raced a Shell Valley bodied Cobra. When he originally built the car, it was a street car, with the common chrome single hoop roll bar, but when he decided to make it a drag car, he needed to make a NHRA legal roll cage for it. Technically, the cage is supposed to be welded to the frame, but John came up with an interesting idea, he welded up a double hoop roll cage, which ran through the fiberglass body, with a drivers side door bar, and since welding the cage solidly to the frame would mean if he ever wanted to remove the body in the future, he would have to cut the bars from the frame. So he welded stub tubes, about 3" tall each, to the frame, and then the legs of the bar slipped over the stubs, and with 2 bolts per tube, at 180 degree to each other, bolted the cage to the stubs. The local tracked let that pass Tech, and a couple of years later, John really put the cage to the test, when during a typical high wheelstand, the car went right, flew up over the concrete guard wall, and flipped over , hitting the top of the wall with the main hoop, and eventually landing on its tires again, on the spectator side of the wall, with only a dent to the main hoop. I have some photos of Johns Cobra, but I can not seem to be able to post them here, maybe TomP has some as well.