i towed my esky from waipuk to gizzy, (bout 4 hours) and we put a chain around the diff on each side, then had a tie down on each side of the crossmember, a tie down on each side at the back, and an adjustable winch from the crossmember in the middle to the front of the trailor.
car didnt move at all, bout half way the winch came a little loose but we just clicked it back up and was fine.