Just a quick check,push the height knob fully home,then pull it out one click,then loosen the cable on the disc. Move the disc so it is lined up on the hole and notch. tighten the cable ,then pull it right out . go for a slow drive of a couple of miles and push the height knob back home again. Is it still high? If so ,the main valve is sticking . You may need to do this a couple of times to unstick it. . Normally the disc notch is only half over the hole in the valve body or covering it as in this example. nearly every 6.3 I have ever seen is like this.