The recommended method to convert these disks is to upgrade the operating system to Windows 10 first, then perform the MBR to GPT conversion. So 2k8 sounds like a no no even for an offline conversion.

You can convert an MBR disk into a GPT disk using the Windows interface. After backing up or moving the data to a GPT disk, right-click each partition and select Delete Partition or Delete Volume.

This disk management software can convert MBR to GPT without losing any data. Check the table to learn how EaseUS Partition master makes MBR to GPT conversion safe and worry-free: ...

Many computer users are curious about whether they should use MBR or GPT when initializing a disk for the first time in Windows. In fact, selecting the appropriate option is essential for the ...

Doing so causes the GPT partition table to overwrite the data on the destination drive. To resolve this issue, the user needs to convert the GUID Partition Table disk to MBR.

GPT supports a "protective" MBR so that third-party MBR utilities can identify the disk correctly, as well as a "legacy" MBR if the first partition must boot as an MBR drive. See UEFI and MBR disk.

Turns out by default Linux (RHEL8) is still using MBR disks and so you run into the 2TB max limit. Found that there is a command "sgdisk" that will do a live conversion to GPT without any data loss.

This disk management software can convert MBR to GPT without losing any data. Check the table to learn how EaseUS Partition master makes MBR to GPT conversion safe and worry-free: ...

Many computer users are curious about whether they should use MBR or GPT when initializing a disk for the first time in Windows. In fact, selecting the appropriate option is essential for the ...