We don't use a "double flare".
Older British cars have a bubble flare (aka Girling flare) backed up with a male swivel nut or a 45 degree double flare backed up with a female swivel nut. Metric cars have ISO bubble flares, where the pipes and threads are metric sizes rather than inch.
All TR7/8 brake lines are 3/16" and use a metric "bubble flare". The rear wheel slave cylinders use a long male swivel nut to hold in the line.
To convert from the line running into one cylinder and over to the other, you need a T-fitting. However, if you aren't picky and are re-using the old lines, you can fit in a std American 3/16" T with a double flare. Main issue is that the old lines tend to split when you try to re-flare them.
You can buy all new British fitings, etc from:
http://www.fedhillusa.com/
I welded a tab onto the rear axle, hand brake cable swivel bracket and mounted a T union there. Ran a brake line from the flex hose to it and then to the rear brakes.
I'll try to get some pics up, but I think Beans has some on his web site that show exactly what to do.
p.s. - NEVER use American single flare, or a compression fitting for a brake system. To easy to leak.
Martin
