Since I do not know of an "active" car repair group, maybe some home
repair people might know the answer. I sure would like to know of an
active car repair group.

Anyway, I drained the radiator on my 96 Mustang GT. My car manual
says it holds 14 quarts of fluid. I had a gallon (4 quarts) of full
strength anti-freeze. I wanted to shoot for a half and half solution.
According to my math, I should have been able to pour the entire
gallon in the radiator and fill the empty container with a gallon (4
quarts) of water. That would have taken me to 8 quarts. I should
have been short 6 quarts of mix.

The car took the 4 quarts of anti-freeze and most of the gallon of
water. I am guessing that the engine still had 6 quarts of water in
the hoses or in the engine somewhere.

What is the proper way to completely fill the radiator? Car running?
Heater on?