have you not seen how a big bike carbs are setup - their throttle axle is one item. One bell crank - one cable one twist grip on the handle.
tuning multi carbs is not cakewalk -you need to go real oldschool to tune it - air flow, timing advance, exhaust temperature per port - I mean real oldschool mod stuff. When cars would launch hard enough to rip out tarmac (hemi 440 can do that)