Still a user active link here: [Request] NVMe BIOS mod for MSI X79A-GD45 (8D) - BIOS/UEFI Modding / BIOS Modding Requests - Win-Raid Forum (level1techs.com)
EDIT: Sorry my bad, indeed its not for the PLUS.
Do yourself the mod, guide here: [[HowTo] Get full NVMe support for all Systems with an AMI UEFI BIOS - Special Topics / NVMe Support for old Systems - Win-Raid Forum (level1techs.com)](https://winraid.level1techs.com/t/howto-get-full-nvme-support-for-all-systems-with-an-ami-uefi-bios
Im not near a system and/or my files to share it again.