I could be wrong, but I think the King V was actually bigger, and the first one was made for Robin Crosby, because he was a pretty big dude.
That first guitar definitely had a more "squat" shape to it. Jackson did a limited run of those that the called the "short wing" back in the early 2000's if I remember right. I believe they were supposed to be limited to 200 pieces, 100 were string thru and 100 with trem. I think the majority of them went to Japanese collectors, so if you see one in the US they are pretty rare.