ViseGrip yes, the needle nose version no. I'd use a flat jaw version if the nut still has sides and a round jaw version if not. Use newer genuine brand vise grips with sharp/vs. worn teeth so it doesn't slip. Clamp them on tightly and strike them to break it loose. Be careful as they can fly/launch off the fitting sometime.

As far as which line, I'd make it out of ni-cop tubing exactly as the factory shaped the current one. I'm assuming correct me if I'm wrong you're speaking about hard brake tubing not a hose, yes?

Good luck!!!

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