Secondary Metering Block Calibration

If WOT is rich you can try a bigger HSAB. Those are the outer bleeds on the top of the carb. That would add more air leaning out the mix. As far as jetting the secondary side which I believe you list as a 74 the original metering plate probably has a number stamped on it which you can contact QF and find out what it is jet sized equivalent to. That's all I've got.
Outer are idle circuit, inner are the main circuit.