Brake flex hose nut???

[Szalkerous]

Hey all...

I'm in final stages of SVX restoration, and in the process of upgrading to the stainless steel flex lines, and I have one corner that has a really weather beaten sealing nut on the hard line / flex line connect. We cracked all the rest with a regular open end 10mm wrench, but this one is on there and feels like it may round right off, especially with the open end. I went out and bought one of the 5 point "line wrenches" (at least that's what I called them... auto store had a more official name)..... my question is... what's the risk run by trying to get this off? (Meaning, if I total the nut even with the correct line wrench, what's the scope of replacement? Does the hard line run all the way to the engine bay, or is there disconnects along the way to make the job easier?) Also, given that it's a brake line, is it possible to use WD-40, liquid wrench, PB, etc. on it?

Any recommendations? I'm driving on three SS and one rubber flex line. That spells trouble in my head. I really want to get that off. I have a new caliper ready to go for that side too. SO CLOSE TO SUBY TIME AGAIN!

Thanks in advance for advice!!

-Szalk