Gutting A Car - Do's And Don'ts

[SlowWhite]

I've started gutting my car in preparation for the Cage. And I am just wondering what I can and Cannot take off my car?

Primarily Just don't want to cut something out that I shouldn't. The first thing that popped up is the Brace that Goes between the 2 Rear Strut towers. I've seen it cut out in 2x1G's with cages but I was wondering if I cut that out prior to cage install will it effect the car in anyways. (car isn't driving but I don't want it to bend or bow type thing)