Sure it will work. I'd get the smoke inlet down low as possible and put some sort of baffle (sheet metal "tent" or something) to help divert the smoke toward the middle of the smoker. At the least put a chimney on the end opposite the inlet so smoke goes across the grill.
For your firebox try to use something that's fairly tight and that allows you to have good control over the amount of air getting to the coals, which is the key to temp control.
Doug