I got looking at your photos and noticed that in a few areas that you could use a 90* gusset tabs, The outer part of that cab is not extremely strong. Add a few of the gussets on the outer support rail , to the frame. I am sure you have it under control. was just a thought, not in any way telling you have to set up the cage.
Just a heads up after putting my nova end over end and having the cage save my life. My dad was a huge help in helping me add the little extras that add up in the end.
Plus I need you to add more weight to that flying brick so I can be some what close to the rear bumper down the strip.
Talk to you later.