Bought a small turnbuckle (eye at one end and hook at the other)and "S" hook at Ace Hardware.
Used a snail type air flow gauge to sync at desired idle speed, then attached the eye end of the TB to a case stud behind the distributor and used the TB hook end and "S" to pull down the center throttle arm on the hex-bar linkage to a slight off-idle position; then adjusted the left carb to match the right on airflow.
The turnbuckle arrangement holds a steady throttle position while you swap the gauge back and forth to check flow. Use a small off-idle throttle opening for best results (least error differential between both carbs).
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