Rounded banjo bolt on rear brake line

I rounded my banjo bolt on the rear brake line of my 95. I found out only after I rounded them that they make a special wrench for this. How can I remove the bolt??? Vice grips just make matters worse. I am trying to install my rear s.s. brake lines.
Ben

Might try filing a couple of flat spots, giving it a rap with a hammer and trying the vice grips again.
As a last resort, I might try some heat. Probably gonna cook something, but sometimes, you gotta do, what you gotta do.

Will do. If I mess it up too bad is it possible to splice into the hard line? I was thinking I could weld two pieces of an allen wrench on either side and twist it out. How bad will the heat be for the brake fluid?

Probably cook the fluid black, probably be a good idea to do a real good bleed when your done and maybe again a couple of weeks later.
Heat will probably soften the metal some. Not really advisable, unless you have to. I try to heat as little as possible.
I´ve been lucky, I´ve come close to catastrophy a few times, but always managed to get things loose, without snapping anything off. Only use heat as a last resort.

Brake flares are hard to do well, takes some practice and a special flaring tool. I´ve silver soldered brake lines together, on fun trucks (not for the street) have never had one fail. Don´t think I´d do it on my daily driver though.