Just put a spring on my a/f screw, and now I'm not sure whether or not I have it set correctly. When attempting to start the bike, fuel constantly runs out of the drain screw on the bottom of the carb.
The a/f (pilot) screw will not cause fuel to leak; that is likely a stuck float or float valve, causing the carb to overfill.
Once you resolve the fuel leak, then adjusting the pilot screw is fairly straightforward, if you have an ear for subtle sounds. Just turn it in until the engine slows down a bit, note the position, then turn it out until you hear a stumble or it slows down on that side. Set it about 1/2 way between those two points, ride, and use small tweaks after that. Once it is really warm, if you raise the rpm then release the throttle abruptly, it should settle directly to idle. If it stays up a second, then settles, it is a bit lean, so turn the screw CCW a small amount; if it drops below idle then comes back, it is a bit rich.