Making Updated ISO from Dell OEM ISO

Hi

I'm trying to update the latest Dell ESXi 6.7 ISO (build 15160138) to include the updates and patches included in the latest ESXi 6.7 release build 202004002.

I've downloaded the offline bundles for both builds in zip format and tried using Auto Deploy in VCSA but keep getting the error:

Invalid Fault

ThrowableProxy.cause

'name'

I'm using VCSA 7.0, don'y know if that's got anything to do with it?

Thanks in advance for any help.