so, i bought a 91 ex wagon with 210k on it. the auto fluid is very dark brown and cloudy. i thought i should flush the whole system with the pull the return hose method. then, i thought the filter must be shot too. so i called a place and they told the the filter is impossible to change without a tranny rebuild. true? and has anyone done this ghetto-flush method that can tell me exactly what to pull and how often to restart the engine and refill?

thanks