dont even bother with rags...a little water is NOT going to hurt a tranny. Pressure was the hell out of it and then DRAIN IT before putting fluids in it. If there is fluid in it already then leave it, pressure wash it, then drain it and the water will come out with the oil. The water really wont even get on anything except little spots of the diff, its just going to go strait to the bottom and the stacks are not at the bottom.