I had rusted brakes lines on my off-topic daily driver last winter. They can be a bear... I bought pre-made pieces of Cu-Ni line with nuts and double flared ends. A couple of them were too long, so I cut and reflared them. One flare didn’t turn out so good so I redid it.
The line is easy to bend by hand, if not bent too tight. I found that the line can work harden if you need to reshape it after bent.
