Finally got my first UDS to operable and decent looking condition so thought I'd follow up on my earlier post and give some details.
Stuck with a pretty basic and simple design. Cut the flat top out leaving a slight rim inside the edge ring in case the lid may need it. Drilled 3 evenly spaced 1" dia holes at 2" from the bottom of the drum. Burned the drum out; it's previous life was a container for a water soluble machining lubricant and I think the drum had the clear rust resistant liner... plus, why not BURN
After the burn I washed off the entire barrell with water/tide to clean off the burn residue. Next I hit the exterior with grinder and sanding disc, and softened the sharp edge with the grinding wheel.
Next, hit it with 2 cans of high heat rustoleum and rubbed the inside with crisco.
Picked up a cheap kettle for parts, so I hinge mounted the lid after pounding out and fitting the rim on the drum. Also, slapped on some cheap frig magnets for air control.
Used 1/4" tapered head bolts backwards through the drum with a double nut and washers, 3 equally spaced at 2 different grill heights starting at 24" +/- from the bottom of the charcoal basket.