third hole in slider?

Hello, Ive got stock carbs on my 1974 Z1. I noticed inside the throttle slider has three holes inside (not including the center hole for the needle). When I disassembled them, the two larger holes were used by screws holding down the throttle plate. The throttle plate has a third hole as well, but the way the throttle plate and lever need to be installed, the holes are opposite each other. are these carbs assembled correctly? What is this third hole for and should it align with the throttle plate??  

If you've not already figured it out, can only be functional in ONE attachment position. Slide cutaway will be on the Intake side. They started using those plates with the hole in them during the transition from the 417 series to Your 217 series. They used that plate for other machines that require that hole, identical in every other aspect compared to the plates without the hole. The hole in slide is for equalization of pressure behind carb venturi and carb top chamber. Plug it up and slide would move much slower and be crazy dangerous to ride ha. Some common sense and comparison photos for you to stare at. Have FuN!       

Cool, thank you