I used to keep my kingsnakes in 32 quarts rack, I no longer keep kingsnakes but I still keep other colubrids that way.
The setup is pretty easy rack + tubs + thermostat + substrate + water dishes.
Thermostat prob goes on the middle shelf sandwiched between the heat source and the tub.
I kept mine at 73/74 on the cool side and about 83/84 on the warm side.