Ok... So, it sounds (hopefully) that this can be a situational issue. Is a horse that is willing to turn butt and kick more likely to kick in other situations that he might not like (such as farrier, saddling, etc)? Or can it really center around one particular event - in this case feed time?

I think we'll do a re-work of his feed time - bucket on the fence to set up a safer situation, whip or pvc to protect me and my space, and he does need some refresher ground work as he's awfully young and green to have been living the easy life as a pasture ornament while I've been out of commission.