Rear Inner Fender Wells

[74Sleeper]

I am getting ready to build the tubs in my car. I am wondering if I can cut out the inner fender wells in the rear of the car without having to brace anything. Are the fender wells a huge structural portion of the rear of the car? I have a build thread going in Project Journals (74 Street Car) if you have any questions about what my build looks like. The tubes going over the rear tires have been removed at this point, they were just a place holder while we put in the frame rails and they have since been removed.