I tried the drawer first, but it got hotter than I liked. 

Edit to add: 

Looks like I made a video about the original smoker with the fire in the drawer.watch

I dug a hole about 5 feet away, lined it with brick for a firebox.

Then I buried a smoke tube (an old hog trough turned upside down) just under the ground, with a smoke hole opening under the stove.

I used a 2" holesaw to make holes up through the bottom, and allow venting out the back.