hitboxes, as in how the character attacks? or hitboxes, as in how the character gets hit by attacks?
if it's the first, then that's a PSA thing, and there should be some help in the Attacks and Animations portion of the forum (i'm not sure if there's a PSA guide or not).
if it's the second, then my guide has some info on it.
http://forums.kc-mm.com/index.php?topic=9248.0 it might be a little hard to do the first time, so ask questions if you need to.