OK, so bubble flare is what I've been referring to (incorrectly?) as
double. And yes, bubble flare brake lines are everywhere in automotive
stores.

The Vanagon system splits front/rear, not diagonal. So you basically
have rear brakes only at this point. :-)

robert feller wrote:
> Is the junction I'm looking for simply a split valve or is this a regular
> assembly too? Anything tricky about it?
>
> Are vanagon diagnal systems or forward/back? I'm curious to what brakes are
> working with my front left "offline".