Ok, here's a pic of the 175 lever (right) vs a 350 lever (left)
What confused me was that I'm use to working on the 350 stuff and I remembered that they had a "continuous" cutout to direct flow from the tank to either the regular or reserve source.
Then when cleaning this 175 tap I saw it had just 2 holes drilled into the back of the lever and didn't notice until now that they intersect at the bottom which allows for fuel to flow between both holes.
Question answered!
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