so ok, a #2 slide and #9 slide have the same cutaways. the #9 is just physically shorter and clears the whole venturi on the larger bore SHA carbs (14:14-16:16)
a #1 slide and a #10 slide have the same cutaways and the #10 is physically shorter and clears the whole venturi too, but is not available really anywhere.
i’ve modified #7 slides to the same cutaway as a #1 slide and it opens the full way and is a good stand in for a #10 slide.
having the carb open the whole way is super important to getting the carb to settle back to idle nice and smoothly.
number 9 slide
number 2 slide