I wonder why the Suzuki folks do not braze that plate to the shaft and remove the air turbulence of the stock screws. Make the throttle body into a two piece junction that slides over itself at the location of the shaft and is held on by set screws that do not penetrate into the airflow. That way you could remove the top of the throttle body and pull out the entire assembly of the rod and throttle plate, put in a replacement, put the top back on and go. Just a thought.