Brendan
Im not sure how much youve gone into this, so sorry if Im teaching grandma to suck eggs
. Dont use incandescent lamps, big mistake I made, far too limited colour range output. In the end I used 4 off 15w halogen (with a tranformer and suitable dimmer), but I think some have used white leds with success. Too much brightness is actually a pain with a CCD, the exposure times can get to less than a second, so go for dense perspex and small lamps for even low level smoothness.
A flat box is a nice piece of kit to have, very convienient .Dusk/dawn sky flats are good, but a pain to capture reliably without full obs automation.