That's superb, although I think you have leeway to inroduce _some_ artistic license here - what about improving the Nacelles (they're a spot-on replica as they are) by putting some black horizontal Bussard Intakes at the front of them? The original Oberth looked daft (as did the Excelsior) without them...
Oh, and are you going to texture the vent/sensor indentations along the forward edge of the Nacelle Pylons/Underhull?
Looking great so far anyways
