Overlooked by that guide is the idle mixture screw, which needs to be removed and cleaner sprayed through. It's on the side of the carb facing the pull start. Compressed air along with a strong cleaner, like Berryman Chemtool works good. The plastic cap mentioned earlier is on this screw. Pull it off and toss it. It's an anti tamper device that limits your ability to adjust the idle mixture right. After cleaning, turn it in till it seats gently, then turn outward 1.25 or so turns. Adjust from there at idle.
To Invent, you need a good imagination and a pile of junk. (Thomas Edison)