So, i was poking around underneath and noticed my hard lines to the rear are in real bad shape, ie. rusted out and leaking. The whole section where they run parallel to the fuel lines up to the LCM bushing is a disaster so I thought about replacing the whole damned thing rather than just try to splice near the firewall.

Each rear line comes in 2 sections that couple at the firewall. Is that coupler necessary? Does it do anything other than join the lines together? Can I just run single lines straight to the master and bypass that thing to make life easier?

 

You're still going to have 2 lines to join. I'd stick to the factory layout.
Do not splice brake lines, never use compression fittings.
Go from a threaded port to a threaded port.

 

That's the thing, I'd rather not go to that connector if it's not absolutely necessary, since it's a royal PITA to get to. I'd just go caliper to master - it would make routing a hell of a lot easier. The real question is whether that connector serves a purpose other than connecting the 2 sections of each rear line.

Thanks!

 

Sounds like the proportioning valve which you need.