WOW! So yours isn't quite the barely cut build as mad darts? you may want to look on into re-enforcing the shock upper mount since you just cut off most of its support.
Not with a 5" DP and a Bigblock!! Not a Novice here. I have raced 8 second 1/4 mile cars for quite a while
I have already come to realize its gonna have to have a cage in it anyway so I will be running a tube from the front outside of the frame rail across the top of the shock tower and to the firewall with a 6" plate. Then on the inside of the firewall another 6" plate and that will be tied into the downbars of the hoop. It will be for my safety more than being NHRA legal. I will install a custom cage in it that will follow the roof and drop near the rear of the 1/4 glass. It'll be sweet!