Okay, I just saw the more thorough explanation. I think I get what you're saying about how you want it set up, and my suggestions won't work that way. Honestly, you're going to have to figure this one out yourself, I think.
Unfortunately, the manifold you have limits your options - ironically, it means you have to be creative in how you set it up. What you want is a simple, geometrically perfect (as much as is possible) rig. And I don't think that's quite possible with the manifold.