OMG, that seems list SOOOOOO much work.
I 2nd Inline tube, they are right by my house, they do excellent work, they will make a complete pre-bent Stainless steel brake set for your specific vehicle and year for $200. Why would you ever crawl under some rusty old truck and fight and break knuckles pulling off 20 year old brake lines??????
Mabey it's a rustbelt thing, but there's is no way on God's Green Earth you'd even get a set of lines off a 20+ year old truck. The line clip bolts would be rusted/fused to frame, the lines would be rusted and bulged at each clip point, the line flange nuts would be fused to the lines. It took me a day and a flare tool and some new line nuts just to bleed the brakes on my '80 sunbird and that was in 1988. The lines were already so far gone, they should have been replaced. I couldn't get a bleed nut to move to save my life, so I had to replace the wheel cylinders and calipers, and to do that, to avoid twisting the heck out of the lines, I had to just cut them, re-flare and install new parts. Perhaps it's different in CA?