Two BIOS files, one modded with microcode 49 and one with microcode 57.
Updated option roms:
Intel RST 17.0.0.3720
Intel LAN EFI 0.0.22
Intel Boot Agent 0.1.13
Please note that it may still be necessary to update to an unmodified version of 1602 first before flashing the modified version, as I already had 1602 flashed before I attempted the mod.
Both tested and working fine.
Files are available here