stick a small screwdriver into the top cover looking thing, dig deep, and pry it up. the lip that holds it in is almost 3/8 deep. After that comes off, there is a 10mm or 12mm socket that is down in the hole that you just uncovered. It must be removed. Then turn the knob (itself) counter-clockwise till it comes off. Ill be happy to help ya if this is not clear just pm me. Its alot easier than it sounds.