That's how mine was when he was younger, though probably to a lesser extent. That's what I meant by "it's best to let him think he's calling the shots." When I stopped "holding" him, (that is, grasping him and trying to keep him still) and started just "supporting" him (opening my hands and allowing him to move about freely, while guiding him towards a general direction) that whipping around stopped. He was never bad about it -- he's always been a pretty calm snake. But, he improved a LOT when I stopped grabbing at him. Even when I take him from his bin now I will hold my hands over him in a "tunnel" shape that he will want to crawl through. Once he's in my hands I can lift him. He doesn't oppose to coming out this way.
I guess it must sound ridiculous, but try it and see if it doesn't help.
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To the OP: I'm sorry, you had asked about cage size and never got an answer. Because mine is still so little he stays in the 32q tub. However, I am having a custom 4' x 2' x 2' enclosure built for him when he is full grown. I am hoping that will give him enough room to roam. I may decide to go a bit larger in the end. Partially because I don't have to worry so much about heat and humidity, so why not go bigger? And partially because he is pretty active and I think he would enjoy the extra space.