Holley instructions contradicting on fuel bowl level ??

I too would not spend any money on new inlet valve until try adjusting what is there.

The small sight plugs, fuel is around the bottom. On older and OEM carbs, you may find different hieght plugs for the priumary and secondary bowls.
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The large sight glass bowls, fuel level is about centered in the glass.
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Not sure what you have there in that photo at the top.
Check it this way:
Fuel level should be around the top emulsion hole. Definately should be below the angle passage to the boosters.
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Take a pencil and draw a line parallel to the ground from the bottom of the sight plug to the side of the metering block.
Take the bowl and block off and see where that pencil line falls.

Draw a line right from the outside right across the face if you have to.
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Set the fuel level dry by turning the bowl upside down, adjust the float so its about level, that should get it ballparked.
In this photo you can see the casting line is about even with the bottom of the site plug.
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Here's a photo of the Udusting nut, the lock screw and the the two washers mentioned earlier in the thread.
These happened to by nylon washers. The good news is they won't tear up easily.
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The downside of nylon washers is they can get a little soft with enough heat.
So I'm not a fan of nylon washers anymore - not in situations where they can get heat soaked. If your just taking it to the track,and many other situations they are fine. Anyway they will work, unless they get too hot. Just have some spares on hand. The only time I had a problem was after a 4 or 5 hours in hills and brisk interstate speeds followed by getting stuck in traffic at crawling speeds. The ones that went were the bowl inlets , not the ones we're talking about. It just made me cautious as it was plenty of fuel on the intake - could have ended real badly.