well steve is some of the way there with his Katy project.

http://www.bigmessowires.com/2014/11/17/68-katy-68000-linux-on-a-solderless-breadboard/



He has a ROM already made up for Katy,  granted, none of Katy  (other then the 68000 cpu) is Apple specific,  but it might be kinda interesting project?

Mac Plus these days you can still pick up for reasonable amounts of money, and with bbraun's PS/2 mouse/keyboard adaptor

and now with complete control of the ROM... + bbraun's adaptor, might bring some non apple guys to vintage apple hardware?