Compact Macs always were just a bit too short for comfortable viewing, as well as effective convection cooling. Apple also made their Compact Mac HDDs and the CD in the Zero Foot Print form factor. There are tons of ZFP designs from other manufacturers. With a different faceplate without the 1U mounting ears, would that long low SuperDuperBox be a ZFP case for a IIx/IIfx perchance?
Very cool boxen, I wish I had a breakout box for my NuBus SAII. The headphone jack out is all I really need in order to choke stereo out of my Duo's. What a PITA that project was!