Scripting

The hard part is recreating the OEM, but why do you even care about it. You will not the data to put back on the oem, just create the primaries.

create partition primary [size=n] [offset=n] [ID={byte|GUID}] [align=n][noerr]

ID={byte|GUID}

Intended for OEM use only.

Caution

Creating partitions with this parameter might cause your computer to crash or be unable to start. Unless you are an OEM or an IT professional experienced with GPT disks, do not create partitions on GPT disks by using the ID=byte | GUID parameter. Instead, always use the create partition efi command to create EFI system partitions, the create partition msr command to create Microsoft Reserved Partitions, and the create partition primary command (without the ID=byte | GUID parameter) to create primary partitions on GPT disks.

use something like:

select disk 0
clean
create partition primary size=750
select partition 1
active
assign letter=d
create partition primary
select partition 2
assign letter=c
exit