To follow up on this, I’ve now put my step by step description online:
I wanted to run through the full process and add some helpful screenshots as well, but couldn’t set up any new VM instance since Oracle Cloud was out of capacity in all availability domains I have access to:
So for now this is written based on my memory and on using Ctrl+R a lot. Improvements are very welcome, I’ll also retest from time to time whether my Oracle will add some more capacity in my home region.