IT IS ALWAYS FASCINATING to see the steps behind making an amazing illustration. Case point: Kevin Hulsey's stunning cutaway of the Radiance of the Seas. As he modestly states: "Size: 36" @ 350 dpi, 640 mb CMYK File with 35 Layers / Illustration Time: 720 hrs."
Yes, 720 hours. That would be one month. Solid. 24/7. No breaks.
If he can put in those kind of hours, you can put in the five minutes it takes to read how it was done. Well worth it.
Detail from Illustration Above