You fill, when warm, up to the fill hole on side of the transmission.
If "cold/cool", fill to about 1/2" below the fill hole on the side of the transmission.
You might have to check the level in the transmission a few times after opening/closing-sealing the torque-tube ball. It take a little time for the transmission oil to level out from the transmission back to the ball; AND, you most likely will leak/drip a little (I carry/use a disposable diaper, to keep drips off people's' driveways).
