Here's what a Ranch looks like with a chunk of a 22" kettle being used as a vortex. I use this set up to smoke large briskets overnight. The "snake" of charcoal will go almost 1/2 way around in the 6-ish hours I sleep.
I guess it really isn't a vortex, but more of a ring to keep the charcoal along the edges and a place for a drip pan in the middle.
The problem with trying to make a vortex for a Ranch is that the distance between the coals and the cook grate isn't to scale for the size of the grill. In other words, the coals are a similar distance to the food as how it is on a 22" kettle. if you had a vortex in the middle of the grill, it wouldn't be large enough to make extreme heat like it does in a standard kettle.