Isn't it a kind of odd shape for a funbox? Not trying to diss your idea man, looks like a sick setup! I just think something like this (but with a rail obviously) would make more sense: www.pinkbike.com/photo/5350896
The flat section would mean you could grind up and down the rail, not just down. And nose manny the flat inbetween the banks or whatever.
Ahhhh fair enough. Man that's actually pretty sick! I imagined it being kinda cramped and sketchy by looking at this, but you're right, it'll work. sweeet