I’m gonna continue the conversation here to not spam the other thread.
You can try payload_dumper, that script can create new images by combining factory images and an OTA delta update. I haven’t been able to create trustworthy images with it so far, I wouldn’t try flashing them. They’ll need to match the hashes the system expects…
I’m hoping for payload-dumper-go to get support for it at some point, that one has been much more consistent and stable.