I'm looking to put together a '040 machine with an Apple IIe card. From what I know, I think I want to find a Quadra 605, put a real '040 in it, and overclock it to 33MHz. Is there any reason to look at a 575, perhaps for the mb? Will the 575 mb fit in a 605 case? Is the only real difference between the 575 and the 475 the MHz gap and the existence of a comm slot on the 575? Other recommendations?