Noah wrote in to share some cutaways of nuclear reactors found on the Wired Science blog. Apparently these posters were published by Nuclear Engineering International during the 1970s and 1980s. Illustrator John Way seems to be responsible for most of them, with one by Dick Ellis, and one uncredited.
Click through to the U of NM link for very high resolution versions. Apparently there are about 100 posters waiting to be scanned so if you’re interested, keep an eye on that link!