Kiln design.... Ideas??

I have been thinking of design ideas for my drum kiln.  I have these two 55 gal drums that a welder friend of mine was going to cut doors in, and ended up welding them together...end-to-end!  So I am making lemonade (metaphorically speaking).  I thought that I should put two top loading doors (one on each drum), and attach a brick firebox to the bottom of the front with a thick steel pipe.  The inside of the drums will be lined with 3-4 inches of ceramic blanket.  Here's a quick drawing to show you what I'm thinking. Please let me know if you think this is feasible.  I figure that this way, I could actually pick up the metal drum part of the kiln and store it inside - out of the rain, while leaving the brick firebox in place outside (wrapped in plastic when not in use).  It would also allow me to use it for wood with the firebox, or gas without the box.  As I said, any suggestions or observations would be very helpful.
 Note: sizes on the drawing are not to scale...some ideas of proper scale would be greatly appreciated!