Easiest thing you can do to figure out what?
I think dual intake into the same port is a different situation here performance wise because it's effectively very similar to just adding a bigger carb at that same location. Are you talking about the Y shaped intakes? With 1 set of reeds? I feel like dual carbs on separate intakes in different locations of the crank case, both using different types of induction, is quite different and probably much more challenging to tune.
That throttle cable looks like and uses a very similar mechanism to the one that came with my pinasco kit. The knarps are huge and would need some grinding/modification but I think I may just pick one of those up just in case. Thank you!