Leaking brake line

I have a 1994 ford mustang with a 3.8 liter engine. i have notices a leaking brake line but for some reason it does not leak all the time. the spot for this leak is located underneath the radiator it has 2 brake lines that goes beneath it. when i see a puddle about the size of the bottom of a pop can i have reached up to feel the line and it is dry as can be but is brake fluid on the ground. i put new rear brakes,calipers, and rotors and has a mushy pedal i bled it and still seems to leak randomly. the line is always dry up to master cylinder. also on a note the master cylinder has remained full even after having bled the system any help would be awesome cause i want to start driving it again

Welcome to AF!

What is the color of the fluid? If it is a brake line it should be clear. If it is one of the lines running from the transmission (automatic) it should be red.