I’m pretty sure you’re going to have to use a live USB. You can’t modify a partition while it’s mounted and you can’t unmount a partition that’s in use.

Just go with Mint. However, if you want to get the most out of the device, you’ll need to use linux-surface and that will involve a little command line usage to setup. Fortunately, the project has detailed instructions..

The title screen music from Katamari Damacy.