Hi guys,
I'm getting into the carbs on a '67 250S automatic with the dual Zenith carbs. The PO must have been "fixing things". The front carb had only one "Mixing Tube" labeled 4N. The rear carb has two tubes - one is a 4N and the other is a 4S. Shouldn't both fronts be 4S and both rears 4N?

If so, I need a second 4S for the front. Anyone have one available?? Who is a good source for rebuild kits? (Any chance the mixing tubes would be in a kit? Ha!)

Also which jet should go where? My Chilton manual is less then clear as to which jet is which. "Idle Fuel Jet", Idle Air Jet", "Air Correction Jet", "Main Jet", ...which is which and what number goes where?
Help!
Dennis