I was always taught that the birds should be 26 inches above the BOTTOM of the fire.
Gotta go find my recipe from the early 1960’s for the sauce. IIRC the current recipe calls for much less salt.
When I first helped with doing Cornell Chicken in the erly to mid 1960’s, we always held the cooked birds in “standard” 40 quart milk cans. The lids were tight-fitting
and would keep the birds hot for several hours. In addition the birds never dried out while being held this way.
Unfortunately milk cans are hard to find today.