(Above left) This screw is covers the hole used when synchronizing the carbs, remove it. Also the air-fuel mixture screw (right).
(Below) Sometimes when removing the air-fuel screw, the spring comes out with it, if not, take a short length of tie wire and bend a little hook on it...pull it out without gouging the threads. At right, notice the whole in the screw. When I bought the rebuild kit, the new air screw didn't have the hole in it as the one below. I put the this one back in after inspecting it for wear. I really have no idea if it's better than the one without a hole, but that's what I did. I'll do more research on this and update the info.
