for this one , make sure you can do a 270 in on a flat box whit your eyes closed.
you need to separate your lower body form your upper body . where your lower body gives you the pop needed and your upper body gives you the rotation . has you pop and set the rotation whit your shoulders and arms , look at you noses , when they are high enouff to clear the rail thats when whip your hip and legs to bring them under you and be in a rail position . the more you wait between the pop and bringing the lower body under , the more hight you are gonna get . in other words , the more patient you are the better. get it? let me know if not ...