I got a great shipping rate for a Bridgeport mill but I need to pick it up at a trucking terminal. I plan on using a "roll back" tilting flatbed car hauler to get it from the terminal to my shop ~$60.00. I am hoping I can slide it back down the bed and in the doors far enough to close them. But my question is: has anyone had any experience doing this? I don't know the minimum angle the roll back can maintain without tipping the crate over. It will be well crated from the seller. I will tell them to lower the knee and invert the head. I wonder if I need another line attached to the top of the crate to prevent tipping. The crate is 68x56x85".
Any words of wisdom?

Thanks
Steve