Yes, you need a 2D surface to project a image accurate. But if the depth of the object, or a obeject's given área it's not very variable, and if you Project the image with a projector very very far, it can help a bit.
Well... ok, another (better) idea:
-Print a quality transparance of the lateral diagram with the lines etc.
-Place it over a frame with glass screen in a stand. Try to align it between you, the ship and the glass, in a way the size appers the same and the countorns match for your point of view.
-And ask someone to help, using a laser line to place each line in the right place.
Or perhaps use a vídeo câmera real time monitor, shooting from far, Split screen with the live image from câmera and a photo from the diagram. He would working near the model, and all the time looking to the monitor image shoot from distance with the diagram on the side of screen. So he can work closer and see how the model is getting in full image, in magnitude.
With the help of a software, anything but the diagram lines would be visible, and the rest of the diagram very transparente, and it would be placed over the image of the model. So he would work on it and all the time looking to the monitor to see it the right place was got..
Sounds like crazy ideas, but for a talented perfectinonist guy like hin, crazy it's never crazy enough.
If you project a 2-D image of a 3-D image onto a 3-D surface I would imagine the details would be inaccurate. A laser level would be my solution. You could then mark the lines with a scoring tape, or line tape if you intend to prime the lines in, and then you got it! Of course, I am eager to see YOUR solution.