You need at minimum a 32qt tamale steamer, a smokey joe BBQ ( silver or gold). If you have a gold all you need are a few nuts and bolts to create supports for one rack. If you want 2 racks you need another grate and more nuts and bolts.
If you use the silver you need two black pipe nipples and two 3/4" gate or ball valves.
Same nuts and bolts for grate supports.
A sheet of expanded 1'x2' (that's the size carried at hardware stores) for making a charcoal basket. Rebar wire ties if you don't weld to hold the charcoal box together.
There's some other misc parts that are mainly for making vent opening and closing easier.