I discovered the same thing when I overfilled a rebuilt Torqueflite 904 before starting the engine. 2 quarts ended up on the floor out of the case vent! Unless the engine is running once the filling begins, the torque converter will not fill. Once it fills, a check valve in the valve body keeps it from leaking down. Don't add any more fluid until you're able to fire it up!
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
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