More disc brake questions

Some trivia additions to the discussion:

I recall I used standard SAE tube nuts for 3/16" tube on the MC from a 1995 Breeze I used. It had the normal inverted flare ports. Otherwise, a Breeze uses metric hardware. I think metric brake parts start with the "bubble flare" fittings and tubing, starting in the late 1990's in U.S. cars. BTW, the tubing is "6 mm", but I found it interchanges w/ 3/16" tubing, and I double-flared some, but the threaded ports don't interchange.

My 65 Newport C-body has a factory booster w/ drum brakes. There is no linkage like in post 35 photo of a 72 Challenger. The pedal rod goes straight into the booster. I have changed the booster twice. There is a plate that bolts to the firewall, which the booster attaches to, with a 4-bolt pattern but a different pattern than a 74 Dart booster I had. Other than that, the two boosters were almost identical - same diameter Midland-Ross, except the cylinder thru the base-plate was a different diameter.