It sounds like this horse has right-brain times & then flips to left-brain (fearful to confident & thus looking to take over leadership): the shaking in fear in his stall can't be faked, as well as going starkers & hurting himself. If he does indeed have this complex "horsenality", one must be a very capable horseperson to adapt to his quick emotional changes & deal effectively with them: when he's scared, you must be reassuring & a confident leader for him, when he's playing you, you must be firm, but without getting mean or angry with him.
I don't like cross-ties, accidents can happen easily in them, horses can't turn their heads so feel claustrophobic, (perhaps his message there reached you) & you need a partnership with a horse so that he can stand quietly for you to groom him, with the lead looped over your arm or ground-tied.
Seems like just grooming him in this way would be a good place to start: you're feeling of him, so that he can feel back to you, establishing friendliness toward him, & not asking him to DO any more than that. Till you've established a friendly partnership to that small degree, you shouldn't go on to bigger tasks.
It's never the horse's fault, we must remember that always.
I suggest that you get a rope knotted halter with a 12-14' lead, also, so that you can stay safe & have some leverage.
Last edited by Northern; 06-18-2013 at 04:13 AM.