Maybe I'm out in left field on this but I'd run new lines (Ni-Cop) and be done with it. One nice thing about earlier systems is no fancy flares, just standard double flares and flaring tools (I have a Rigid double flaring tool) aren't all that expensive either.
Learned the hard way with my 97 about OEM steel lines and what happens to them as they age, they corrode. Not an issue with Ni-Cop and Ni-Cop is easy to work with too. Comes in a roll so you just unroll it and bend (by hand) to fit. I did my entire brake system from master cylinder to all the wheels in a weekend.
Best part is, I'll never have to do it again. Ni-Cop is forever.
