Grip the teeth of the adjustable wrench around the female fitting of the two pipes that are rusted together. Attach the second adjustable wrench around the male side of the fitting.
Encircle the handle of the wrenches with the 2-foot-long PVC pipes to gain extra leverage.
Have a friend hold the wrench on the female side of the fitting. Put on your gloves. Firmly grip the wrench on the male end of the fitting. Hold the wrench so that it is about 90 degrees from the other wrench.
Forcefully press the wrench you are holding toward the wrench your friend is holding. Forcing the wrenches together turns the male pipe left, loosening it. If this worked, continue to loosen the rusted pipes until they separate. Otherwise, continue to the next step.
Put on your protective eye wear. Plug in the Sawzall equipped with a metal cutting blade. Cut the male pipe about 7 inches from the connection. Repeat this process for the female end.