Question about flares and fittings

[65 drop top]

I had a shop a while back bend me up some stainless lines from the master cylinder to a distribution block. I wanted to remove the lines to polish them up. After thinking about it I think there's a problem. First of all the distribution block is a brass block designed for double flares. I'm assuming the shop I used couldn't double flare since they used an fittings at the master. They used an an fitting into a banjo fitting at the distribution block. The banjo bolt snapped off when I tried to unbolt it. So is a banjo fitting safe to use at a distribution block designed for double flare? My concern is that the banjo bolt might bottom out before it compresses the crush washers. Maybe not seal properly at the distribution block? How do I fix this, should I get a new line bent with double flares? Do they make a double flare to an an adapter?

[MonzaRacer]

The banjo bolts will need to be checked for length, BUT why switch? Most of what I have seen are banjo bolts that AN lines hook too. I have a hydraulic flaring tool and wound up getting a set of 37 degree AN flaring dies.
BUT the actual issue is learning the thread pitch/type of double flare. There are US which are 3/8, 7/16 etc. Most are fine thread.
If you are using a newer say Corvette style master cylinder it might be metric threads which means you need metric banjo bolts.
I have ,on my other computer, where to source such items. Ill see if I can find it when I get back home.