If I use the middle tip of the w gauge it is longer than the sides. The other sides of the gauge are flat. I was using it as a reference as you use it for wt carbs.
In your pict above there is a bump out marked WB, that is the gauge to be used on this application, of course use it on top of the metering gasket as already posted, has worked fine for me now on correcting 4 of the 362`s including my own.