The mid needle is set from the factory flush with the body of the carb.
It could be that your lsn is still a bit too rich. lean it out 2 hours. do a couple of full throttle passes and stop the car. let it idle for a few seconds and then pull the trigger to the max. if it hesitates a bit and then takes off like a "bat-outa-hell" , your lsn is pretty close.