Welcome Francisco.
A couple thoughts on rib hanging. I use the Hunsaker rack in my WSM 18.
The end closest to the fire will get cooked less than you would think. So you can just do nothing special. You'll have one rib that is crunchy but still edible.
Second, you can flip them as Joe suggests above.
Third, in a 22 you'll have plenty of space unless you are cooking a crazy amount of ribs. So I find it easiest to cut the slabs in half, and then cook six or 12 half slabs instead of three or six full slabs. The half slabs are a bit easier the handle, and the reduced weight means no worries about the cooked ribs getting so tender that they pull off the hooks and go into the fire. With halfs, one hook is fine. With full slabs, some people feel the need to double hook. To keep falling ribs out of the fire, some folks will put a cooking grate on top of the coal ring just in case.
Diffuser plate or not is mostly a question of taste. With no diffuser, the fat drips into the fire as with a PBC type drum cooker. I like my ribs that way. Some folks use a diffuser to avoid that taste. Personal preference. If you go with the half slabs, you probably have enough space to use your regular diffuser (water pan (empty or full), firedial, plant saucer, pizza pan, whatever).
Last, I just cook them on the hooks and dispense with foiling. Unhooking, foiling, reinstalling the cook grates, etc. is too much trouble for me. What I like about hanging ribs is how simple and easy it is, and how much cooking space you have with stuff being vertical. Wrapping and going horizontal undoes a lot of that.
