Since my Duster will be running in stock class I ran my bars similar to 6pk s but I ran the trunk bar back to the top on spring box. In fact both front and back spring boxes are tied into the cage. These places are where your car rotates from so they need to be strong. I also have bars going to top of shocks from those back bars. IMO you want the car as stiff as possible with the least amount of bars, a triangle is the strongest configuration in the universe.
My rear trunk bars tie into the rear leaf spring perches and has a bar tieing them between the frame rails that is also my parachute mount bar as well. I also have bars running down from my main hoop through the floor to the top of my front leaf spring perches as well. Unfortunately, they punch right through the rear seat though.
