I have mine at 5" below and 12" below the lip using a weber lid. This way I can get 2 butts on each rack without touching the lid or easily do beer can chicken on both racks. I have the bolts in place for the optional flower pot heat diffuser which lets me run it exactly like a WSM or take it out and just use the top rack traditional UDS style.
Neil -- "Easy Bake Master"
NB Bandera [gone to heaven...conveniently located in Long Island, NY]
Rebel 23, WSM A, WSM B, UDS, Easy Bake Oven
Pork Pistols BBQ
MOINK...It's what's for linner.