[G.A.S.]

make sure the master is full. jack it up and pull the tire. Have someone sit in the car, start it and pump the break 2-3 times and push down on the peddel and hold it down.While your helper is holding and pumping the peddel, watch and listen for leak.
there is a rubber hose that goes from the caliper to the frame.
start by checking for leaks near the caliper, work your way up the hose to the frame, at the connection at the frame the hose hooks to a steal line and that leads to the preportioning block. this is under the mastercylinder hooked to the frame. You should see fluid leaking somewhere in that area.
Break fluid is water solubale so if you have a big mess on the car take a garden hose and spray it off and let it dry and start over, that is if you dont see a leak that is very obvious.
90% of the time it is a steal line between the hose and the preportioning block. If your lucky it will be a hose. Much easyer to change