I don't know but it looks interesting. I think I start with getting the inside at least sand blasted. As far as the fire goes I believe you will be using charcoal and running this like an UDS so you will need to seal the door with some high temperature rope. This is important or there truly will be a fire inside it. The size you stated just doesn't seem right according to the picture. It looks like it is 12" deep not 2'.
Making memories!