Forgot to mention, the horizontal bars in the middle of the cross bars, are bolted through 1/4" plate welded to the cross bars. I made 4, and each one can fit into any section of the frame. Originally I planned on drilling through the tube and bolting the braces to them, but I figured this was just a way for water to get inside resulting in rust, and limited me to installing them on to that one location. The way I made it I can bolt them on the inside (most of the time) and it allows the sides to be fastened while using them. Or for easier access I can flip them around and bolt them on the outside of the 1/4" plates to give easier to access to whatever is mounted to them, but this means the sides have to be rolled up or removed.