I used
@CaseySJ guide to move from clover to OC.
OpenCore 0.6.0 VirtualSMC 1.1.5 Lilu 1.4.6 WhateverGreen 1.4.1 AppleALC 1.5.1 NVMeFix 1.0.3 With NVMeFix 1.03 , my system can't boot , neither with OC or Clover, but NVMeFix 1.02 seems ok
www.tonymacx86.com
You have nothing to format (except the usb stick).
First create an USB stick with efi partition and configure here your open core configuration.
With that USB stick you are able to test the efi oc configuration. Just boot from the usb stick and look if everything is working. When not boot again with clover.
When it‘s working you can just replace the clover efi folder from your efi partition on the hard disc with the efi folder on the USB stick.
Needless to say that a backup is absolutely recommended
To be fair it was a bit easier for me because I have nearly the same hardware configuration like CaseySJ.
So I haven‘t to deal with SSDT configs.