In my Google travels, I just came across this for sale - purportedly a replica prop from Star Trek Phase II. Here's the sample image: IMO, it's really quite good. They've placed the engine room exactly where Mr. Jefferies original Phase II diagram (as extrapolated by Shaw) suggests it should be, and unless I'm mistaken they have the old engine room up ahead of the impulse engines. I quite like the primordial take on the intermix chamber, which isn't quite linear. (For those not familiar with the Phase II engine room, here's Mike Minor's concept painting, and here's the incomplete set.) I'd love to get a look at that TOS diagram in the inset, too. I don't suppose we'd be lucky enough to have the maker of this lovely image amongst our membership?