I just wanted to let you know that even after our great discussion, I ended up buying a brand new Caltar II-N 115 a moment ago for $500. I figured I couldn't pass up that deal. Worst case scenario, I sell it for at least what I bought it for and move on to something different. The 115 will let me do all the crazy movements/shots I've been planning, then I can move to something physically lighter and wider (I'll keep this chat in the back of my mind in the future).
I'll post another thread when I start building/assembling my beast (probably around the start of July). Until then, I'm collecting parts and refining my design.
Thanks again for all of your help! Happy shooting!