Elbox FastATA is a IDE controller which plugs on Kickstart Socket (and Gayle) but it doesn't act as a kickstart ROM.
Overall this idea is unncessarily complex. It will be hard to configure a mass storage drive to act both as a Kickstart ROM and IDE drive. better to seperate these functions into two simpler boards, the IDe drive (which is available for 68000 socket) and kickstart flashable ROM (available as some hobby projects.)
