The main roadblock is that many installers from 2003 contained (usually setup.exe ). While 32-bit versions of Windows could run 16-bit code via NTVDM, 64-bit Windows has no 16-bit subsystem at all.
qemu-system-mips64 -M magnum -kernel vmlinux -hda irix65.img \ -append "console=ttyS0" -nographic magics 2003 64 bit install