See mine
http://eab.abime.net/showthread.php?t=24707 I wanted something specifically to fit the Prometheus without sacrificing additional Zorro slots, it worked. Though most cases are not designed for upside-down board mounting, nor do they have removable top panels, so it's not entirely a practical solution for retrofitting a standard ATX case. A removable card cage/backplane like the dell one would work, but the insertion force for the A4000 daugterboard is quite high, I'd be concerned about causing stress fractures from repeated installation and removal