1966 Mustang Helix suspension

Hey guys I bought the Helix Mustang II IFS kit for my 66 coupe and I need help with the measurements. The instructions are really vague and don't give the proper measurements to cut the front suspension cross member and the top hats. Its a universal kit and like I said the instructions aren't much help. Some if anyone has thrown one of these kits on or some like this kit and would be able to help me with the measurements that I need to cut the cross member and the Top hats it will be much appreciated. Thank you.