Follow Up: Why does my new tennessee walker spook on the trail?

This is a follow up; My new, six-year old walker is extremely dancy and spooky on the trail-WAY too hyped up to do anything with him! He's OK in the arena (he spooked once because there were men walking around in the woods that bordered the arena)... but his behavior on the trail has gotten crazy dangerous (I have had the horse for a month, and to my knowledge, have not caused any of these bad habits) I just switched his feed to seniorglo to try to curb some of his energy. I ride my walker in a five inch shank tom thumb bit with a new abetta endurance saddle. I think the bit may be too harsh... any suggestions? I have never allowed him to be barn sour, he just does it out of spite, I guess (I always turn him back up the trail and work him when he tries to bolt, but lately he's gotten too spooky to do anything with!) Because he's too dangerous to ride, I'm just walking him up the trail and cocentrating on ground work. I can't really afford a trainer (I'm broke now) HELP