I used to do ribs on my 22" Weber in a simple manner. I built a charcoal fire and split it down the middle. So I wound up with two small fires on the sides over which I placed the cooking grate handles. I could then add charcoal to the little fires through the handle holes without disturbing the cooking grate. The rack of ribs went down the middle. I called them done when they would do the cobra. By that I mean I could grab the end of the rack with the tongs and lift, and looking from the side the rack would have the "square S" appearance of a risen cobra.
Very similar approach here, but modern Weber grates have hinged openings on both sides, Very handy.
