I've only seen it happen a couple of times but brake lines tend to rust from the inside out....they can look great, right up until they burst. It's one of those jobs I really don't care for, especially doing it on a creeper, bu tthe piece of mind is well worth it.

While It's still up in the air and I'm under there I think I will also be running a new tank to engine fuel line. I don't know if they were all this way or if it's just because this was originally a 6 Cyl but the current line runs down the pass side of the car but on the FE the fuel pump is on the drivers side.