So he was vetted yesterday- and the result is that it is behavioral. Had his back, stifles, hocks and teeth looked at- nothing. Heels okay, nothing bad to report except that he still needs to gain more weight and build his topline. Was kind of hoping it would have been something physical as I could deal with that a bit better but since it's behavioral, have to take this at a different approach.
Rode last night, didn't put up with his BS and am getting after him more when he tenses and acts like a brat and overly praise him when he relaxes.
I switched girths to a double sided elastic girth and added a gel pad. Also went to a jointed Kimberwick from a Pelham and he seemed to like it better. (Pelham had a low port- he hated it!)
So from here it's all about discipline and learning what I won't tolerate. He respects me on the ground. Now he needs to respect me in the saddle. Now that I know it's all in his head, I'll be having some "talks" with him.