Does your LBA48 CD contain support for ATA interfaces beyond the primary and secondary controllers found on the motherboards? Or, does it contain an LBA48 boot floppy disk image that contains MFSTools 2.0?
Sometimes I upgrade by performing a complete MFSTool backup | restore from my current dual drive setup to a pair of larger drives. If booting from CD, the boot CD must support ATA interfaces beyond the motherboard's pair. So far I've been booting from an MFSTool 2.0 floppy, but it only supports 137 GB.