[BigD9146gt]

I have built both welded in and bolt in cages, for the life of me i cannot find a single picture of the bolt in. The cage you showed above looks like something that comes from a factory prep'd car. A buddy of mine has a '60 356 Carrera with the 4 cam engine, aluminum hoods and doors, factory roll cage, lets just leave it at "the car is amazing". The factory roll bar mounts on tubing thats installed on the car during production. The bottom inside of the boxed frame rails get an extra plate on them, then a short tube welded to the plate with a hole cut out above the top section of the boxed frame. It sticks out about 2 inches, which the roll bar then slides on to and bolts to, and the diagonal braces bolt to the back seat hinge recepticals. Its a possibility that your roll bar is that kind of setup.