The adjuster wasn't assembled right, washers should be either side of te 'U' . The angle may be 'tweaked' slightly or bent so right and left don't match up. The adjuster screw can bind on te 'U' edges if carb has been dropped or something? Be VERY careful if you try and bend the adjuster brackets as the brass throttle shafts will break at 'C' clip where shaft enters carb body. I do a LOT of 360 carbs (and a few CB350, CB450 DOHC)
360 adjuster bits often need some work to get correctly aligned but it's a PITA to do without marring or breaking something. Use two pairs of pliers