The reason for finding any leaks first is because they are not always at the wheel cylinders. While resurrecting a Lamborghini Espada, I had to trace the brake lines to the rear calipers before I found the rusted line that had sprung a leak. It ran under the carpet across the rear floor pan right in the lowest part of the floor, where of course any water would soak into the carpet and greatly aid the rusting process.
