Flare Nut Spanner worked a Treat!

The Master Cylinder (M/C) brake line took about 30 seconds to loosen with the flare nut spanner. I did the inevitable bruised knuckle as it let go. I removed the brake line from the M/C and the four-way brake line distributor as it was only about 200mm away.
(Old picture taken during conversion)

I have cleaned up the threads and the line itself ready for re-installation.
I haven't put the new M/C in yet because I took the opportunity the clean up the firewall where the M/C mounts and repaint it. I now have to wait for my bruised right thumb to get a bit better (totally another story) before I put it all back together again. Brake lines cross-thread easily so I don't want to mess it up now. I'll pick a day with good weather later this week (it's gone all wintery again here) and go home from work a bit early to get it done.