need help with roof rack mounting

[AndrewD]

Hi,
I want to put a roof rack above the canvas canopy that will attach to the head board and rear roll bar of my steel tray. The problem I have is how to safely mount the roof rack to the tray to compensate for the issue of sheer force (stopping in a hurry and not having the weight break the mounting points. I do have a few ideas but if anyone can supply me with pictures or direct me to where I can see some mounting options I would appreciate it.
Thanks

 

[fourocker]

Diagonal bracing forward/back comes to mind, in the way the str sports bar has extra legs going toward the rear.