The dipstick o ring and selector shaft seal are are common leak points. Another leak point that is commonly overlooked is the pivot pin for the L/R band lever. I have seen a lot of people "rebuild" these transmissions and not replace it. They will just remove the strut and flip the lever out of the way to take the servo out without replacing the o ring. To most it will look like the pan is leaking when fluid is actually coming out of the L/R pin hole in the rear of the case.